Maximum Axial Position Changing RPM Methods

ABSTRACT

Methods that can be used to “limit the maximum shaft/spline rpm (speed) at which axial position changing of a variator mounted on it is performed to a “maximum axial position changing rpm value” for all variator mounted shafts/splines of a CVT, while still allowing a safe driving experience and also allowing the driver to use the full power of the engine when needed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This invention is a Continuation-in-part (CIP) of U.S. patentapplication Ser. No. 14/929,413, which was filed on 2 Nov. 2015 and aContinuation-in-part (CIP) of U.S. patent application Ser. No.15/055,560, which was filed on 27 Feb. 2016; in addition, this inventionis entitled to the benefits of:

-   -   Provisional Patent Application (PPA) Ser. #62/161,268 filed on        14 May 2015    -   Provisional Patent Application (PPA) Ser. #62/162,807 filed on        17 May 2015    -   Provisional Patent Application (PPA) Ser. #62/204,982 filed on        14 Aug. 2015    -   Provisional Patent Application (PPA) Ser. #62/208,973 filed on        24 Aug. 2015    -   Provisional Patent Application (PPA) Ser. #62/209,338 filed on        25 Aug. 2015

The following previously filed patents and patent applications have nolegal bearing on this application; they describe items mentioned in thisapplication (i.e. cone with one torque transmitting member), but thesubject matter claimed in this application is different.

-   -   U.S. Pat. No. 6,656,070 B2, which was filed on 11 Jan. 2001    -   U.S. Pat. No. 7,722,490 B2, which was filed on 29 Oct. 2007    -   U.S. Pat. No. 8,628,439 B2, which was filed on 29 Oct. 2007    -   U.S. patent application Ser. No. 13/629,613 (Pub. #20130023366),        which was filed on 28 Sep. 2012    -   U.S. patent application Ser. No. 13/730,958 (Pub. #20130130854),        which was filed on 29 Dec. 2012    -   U.S. patent application Ser. No. 13/889,049 (Pub. #20130310205),        which was filed on 7 May 2013    -   U.S. patent application Ser. No. 14/072,390 (Pub. #20140094332),        which was filed on 5 Nov. 2013    -   U.S. patent application Ser. No. 14/082,146 (Pub. #20140141909),        which was filed on 17 Nov. 2013    -   U.S. patent application Ser. No. 14/242,899 (Pub. #20140213398),        which was filed on 2 Apr. 2014    -   U.S. patent application Ser. No. 14/557,454 (Pub. #20150135895),        which was filed on 2 Dec. 2014    -   U.S. patent application Ser. No. 14/597,354 (Pub. #20150126316),        which was filed on 15 Jan. 2015    -   U.S. patent application Ser. No. 14/182,306 (Pub. #20140235385),        which was filed on 18 Feb. 2014    -   U.S. patent application Ser. No. 14/186,853 (Pub. #20140235389),        which was filed on 21 Feb. 2014    -   U.S. patent application Ser. No. 14/475,492 (Pub. #20150233450),        which was filed on 2 Sep. 2014.

BACKGROUND

1. Field of Invention

This invention relates to torque/speed transmissions, specifically tomethods that can be used to “limit the maximum shaft rpm (speed) atwhich axial position changing of a variator mounted on it is performedto a “maximum axial position changing rpm value” for all variatormounted shafts of a CVT, while still allowing a safe driving experienceand also allowing the driver to use the full power of the engine whenneeded. Examples of variators are: a cone with one torque transmittingmember, a cone with two oppositely mounted torque transmitting members,a cone with two opposite teeth, a push belt pulley, etc. The methods ofthis invention are referred to as the “Maximum Axial Position ChangingRPM Method”, the “Alternate Maximum Axial Position Changing RPM Method”,and the “Alternate Maximum Axial Position Changing RPM Method 2” and aredescribed in the “Maximum Axial Position Changing RPM Method” section ofthis disclosure.

2. Description of Prior Art

A CVT that has the potential to replace automatic and manualtransmissions in vehicles is a CVT 4, which is described in U.S. patentapplication Ser. Nos. 13/629,613, 13/730,958, and 13/889,049.

A CVT 4, which is shown in FIGS. 1 to 4, has one cone with one torquetransmitting member mounted on one shaft/spline that is coupled toanother cone with one torque transmitting member mounted on anothershaft/spline by a transmission belt.

A CVT 4 is promising design because it can allow for the construction ofnon-friction dependent CVT's without using ratcheting or reciprocatingmechanisms. However, if a CVT 4 is transmitting a large torque, then thetension in the transmission belt of the CVT 4 is also large. And slidinga transmission belt under large tension from small diameter of its coneto a large diameter of its cone, as required for transmission ratiochange, will also require a large force.

A CVT 6, which is described in U.S. patent application Ser. Nos.14/182,306, 14/186,853, 14/475,492 and this disclosure, has two CVT 4'sfor which the transmission belt tension in one of the CVT 4's can bereduced. Reducing the transmission belt tension in the CVT 4 for whichthe axial position of a cone of a CVT 6 has to be changed cansignificantly: reduce the transmission ratio changing force needed,shock loads that occur during transmission ratio changing, and wear dueto transmission ratio changing.

The axial position of a cone of a CVT 6 has to be changed within lessthan a full revolution of that cone. As such, the duration available forchanging the axial position of a cone of a CVT 6 depends on therotational speed (rpm) at which the cones of the CVT 6 are rotating. Bylimiting the “maximum rotating speed at which axial position changing ofa cone is performed”, the duration available for changing the axialposition of a cone can be increased; and this will reduce thetransmission ratio changing force needed and shock loads that occurduring transmission ratio changing.

For example, when the “maximum rotating speed at which axial positionchanging of a cone is performed”, rpm_max, is limited to a “maximumaxial position changing rpm value” of 3000 rpm; then based on thecalculations in the “Sample Calculations for Axial Position Changing”section below, the initial force needed to change the axial position ofa cone, F_initial, is 40 lbs and the shock loads during axial positionof a cone is h_dropping=0.38 cm.

When the “maximum rotating speed at which axial position changing of acone is performed”, rpm_max, is not limited to a “maximum axial positionchanging rpm value”, then axial position changing of a cone can occurwhen the engine is operating at its maximum rpm. Most car engines have amaximum rpm of about 6000 rpm. From the calculations in the “SampleCalculations for Axial Position Changing” section below for rpm_max=6000rpm, we get F_initial=162 lbs and h_dropping=1.5 cm.

From the sample calculations of the previous paragraph we can observethat by limiting the “maximum rotating speed at which axial positionchanging of a cone is performed” to 3000 rpm, the force needed to changethe axial position of a cone can be limited to 40 lbs. Without limitingthe “maximum rotating speed at which axial position changing of a coneis performed”, the maximum rpm of the engine, which we assume is 6000rpm, will determine the force needed to change the axial position of acone, which for 6000 rpm is 162 lbs, or more than 4 times larger thanthat for 3000 rpm. In addition, at 6000 rpm, the shock loads due toaxial position changing of a cone will also be about 4 times larger thanthat for 3000 rpm.

Without limiting the “maximum rotating speed at which axial positionchanging of a cone is performed”, a CVT 6 can be unpractical forconfigurations where a cone rotates at high speed, such as 12000 rpm forexample. A cone can rotate at 12000 rpm for a maximum engine rpm of 6000rpm and a transmission ratio (output speed/input speed transmissionratio) of 2:1.

The idea of limiting the “maximum rotating speed at which axial positionchanging of a cone is performed” so as to increase the duration at whichaxial position changing of that cone has to be performed is not novel.But only limiting the “maximum rotating speed at which axial positionchanging of a cone is performed” without a control sequence/method, canallow for an unsafe driving experiences such as when the CVT is stuck ina low transmission ratio because the “maximum axial position changingrpm value” is exceeded; or can limit the power of an engine, such whenthe engine is only allowed to run up to 3000 rpm instead of 6000 rpm soas not to exceed the “maximum axial position changing rpm value”.

The “Maximum Axial Position Changing RPM Method”, the “Alternate MaximumAxial Position Changing RPM Method”, and the “Alternate Maximum AxialPosition Changing RPM Method 2” of this disclosure will disclose acontrol sequence/method that will limit the “maximum rotating speed atwhich axial position changing of a cone is performed” while alsoproviding a safe driving experience and also allowing the driver to usethe full power of the engine when needed.

Other Prior Arts

The following prior art that might also be relevant: U.S. Pat. No.7,713,153; Issue Date: May 11, 2010; Patentee: Naude.

BRIEF SUMMARY OF THE INVENTION

Methods that can be used to “limit the maximum shaft rpm (speed) atwhich axial position changing of a variator mounted on it is performedto a “maximum axial position changing rpm value” for all variatormounted shafts of a CVT, while still allowing a safe driving experienceand also allowing the driver to use the full power of the engine whenneeded.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 shows a front-view of a CVT 4.

FIG. 2 shows a top-view of a CVT 4.

FIG. 3 shows another front-view of a CVT 4.

FIG. 4 shows another top-view of a CVT 4.

FIG. 5 shows a top-view of the preferred CVT 6.

FIG. 6 shows front-view of the preferred CVT 6.

FIG. 7 shows front-view of a tensioning pulley 14 that is not engagedwith its maximum contraction stop 15.

FIG. 8 shows a top-view of a CVT 6 that uses an adjuster 8 for eachcone.

FIG. 9 shows a top-view of a preferred CVT 6 for which the adjusters 8are each mounted on a different shaft/spline.

FIG. 10 shows a schematic diagram for CVT that uses a pre-transmission.

FIG. 11 shows a schematic diagram for CVT that uses a post-transmission.

FIG. 12 shows a schematic diagram for CVT that uses a pre-transmissionand post-transmission.

FIG. 13 shows a schematic diagram for Drive System 1.

FIG. 14 shows a front-view of a “Tensioning Pulleys Tensioning System”.

FIG. 15 shows a partial top-view of a “Tensioning Pulleys TensioningSystem”.

FIG. 16 shows a partial sectional-view of a “Tensioning PulleysTensioning System”.

FIG. 17 shows a front-view of a slider mounting plate 20.

FIG. 18 shows a side-view of a slider mounting plate 20.

FIG. 19 shows a front-view of a slider 21.

FIG. 20 shows a side-view of a slider 21.

FIG. 21 shows a top-view of a cone 3D on which a marked disk 26 isattached.

FIG. 22 shows a front-view of a marked disk 26, marker 27, and a sensor28.

FIG. 23 shows a top-view of a CVT 6 that uses a clutch 29 for each cone.

FIG. 24 shows a partial front-view of an adjuster that uses an indexingmechanism.

FIG. 25 shows a partial side-view of an adjuster that uses an indexingmechanism.

FIG. 26 shows a partial top-view of an adjuster that uses an indexingmechanism.

FIG. 27 shows a partial front-view of an adjuster that uses a brake.

FIG. 28 shows a partial side-view of an adjuster that uses a brake.

FIG. 29 shows a partial top-view of an adjuster that uses a brake.

FIG. 30 shows a partial front-view of an adjuster that uses an electricmotor.

FIG. 31 shows a partial side-view of an adjuster that uses an electricmotor.

FIG. 32 shows a partial top-view of an adjuster that uses an electricmotor.

FIG. 33 shows a partial front-view of an adjuster that uses an indexingmechanism which uses a gear train 41.

FIG. 34 shows a partial side-view of an adjuster that uses an indexingmechanism which uses a gear train 41 (gear train 41 is not shown).

FIG. 35 shows a partial top-view of an adjuster that uses an indexingmechanism which uses a gear train 41.

DETAILED DESCRIPTION OF THE INVENTION CVT 6 Configuration of a CVT 6

Labeling for CVT 6 shown as a top-view in FIG. 5: Input Spline 1, OutputSpline 2, Driving Cone 3A of CVT 4A, Transmission Belt 4A of CVT 4A,Driven Cone 5A of CVT 4A, Slider Sleeve 6A of Driving Cone 3A, SliderSleeve 7A of Driven Cone 5A, Driving Cone 3B of CVT 4B, TransmissionBelt 4B of CVT 4B, Driven Cone 5B of CVT 4B, Slider Sleeve 6B of DrivingCone 3B, Slider Sleeve 7B of Driven Cone 5B, Adjusters 8.

A CVT 6 comprises of two substantially identical CVT 4's. The basicconfiguration of a CVT 4 is described U.S. patent application Ser. No.13/629,613. Here one CVT 4 is referred to as CVT 4A, and the other CVT 4is referred to as CVT 4B. The driving cones (which each are a cone withone torque transmitting member and which preferably have the samedimensions) of CVT 4A and CVT 4B are mounted on a common spline througha slider sleeve each (which allow axial but not rotational movementsrelative to its spline) in manner so that the larger end of one cone isfacing the smaller end of the other cone; and the driven cones (whicheach are also a cone with one torque transmitting member and which alsopreferably have the same dimensions) of CVT 4A and CVT 4B are alsomounted on a common spline through a slider sleeve each (which allowaxial but not rotational movements relative to its spline) in manner sothat the larger end of one cone is facing the smaller end of the othercone. It is recommended that the axial positions of the driving conescan be changed independent of each other, and that the axial positionsof the driven cones can also be changed independent of each other.

For each CVT 4 (CVT 4A and CVT 4B), one of its cones is mounted on itsslider sleeve through the use of an adjuster (labeled as adjuster 8 inFIG. 5) that can: a) provide/allow rotational adjustment between itscone and the spline on which it is mounted when needed; and b) preventany rotational movements between its cone and the spline on which it ismounted when needed. The adjuster that uses a gear that is driven by aworm gear, described in U.S. Pat. No. 7,722,490 B2 and U.S. patentapplication Ser. No. 11/978,456 can be used as the adjusters; and here acone can be mounted on its spline through the use of an adjuster and aslider sleeve in a similar manner as a transmission pulley of a CVT 2 ismounted on its shaft/spline through the use of an adjuster and a slidersleeve (see U.S. Pat. No. 7,722,490 B2).

If a cone is mounted through an adjuster, the rotational position sensorthat is used to determine the rotational position of that cone needs tobe mounted on that cone or a portion that rotates with that cone. Therotational position sensor of a cone is needed to determine/estimate therotational position of the torque transmitting member of said cone,which is needed to know when to change the axial position of a cone (seeU.S. patent application Ser. No. 13/889,049).

If desired, a CVT 6 can also comprise of two substantially identical CVT4's for which the cones are mounted on shafts instead of splines. Forthis configuration, the transmission diameter of a cone is changed bychanging the axial position of its torque transmitting member and itsnon-torque transmitting member (if used) while holding still the axialposition of said cone; instead of changing the axial position of saidcone while holding still the axial position of its torque transmittingmember and its non-torque transmitting member (if used) as is the casefor a CVT 6 for which the cones are mounted on splines. For both a shaftmounted and spline mounted configuration of a CVT 4, the axial positionof a cone relative to its torque transmitting member of the cone on thedriven shaft/spline and the cone on the driving shaft/spline can bechanged independent of each other.

Reducing Tension in a Transmission Belt of a CVT 6

A CVT 6 can be operated so that the tension in the transmission belt ofone CVT 4 can be reduced when desired through the use of the adjusters8. Here for the CVT 4 for which the tension in the transmission belt isto be reduced, the adjuster 8 for that CVT 4 allows its cone to rotaterelative to its shaft/spline so as to provide a releasing torque, whilethe adjuster 8 of the other CVT 4 is locked/braked (or provides a slowerrotating releasing torque) so that full torque transfer between its coneand its shaft/spline occurs. If the shaft/spline on which an adjuster ismounted is the input shaft/spline, than the direction of rotation of itscone for a releasing torque is the direction opposite from the rotationof the input shaft/spline. And if the shaft/spline on which an adjusteris mounted is the output shaft/spline, than the direction of rotation ofits cone for a releasing torque is the direction of rotation of theoutput shaft/spline.

The duration that a releasing torque is provided/allowed by an adjusterbefore axial position changing of its cone is started can be based on a“set time duration”. The ideal “set time duration” can be obtainedthrough experimentation. For example, let's say we select the “set timeduration” to be 1 second; here if this duration is sufficient for theadjuster to sufficiently reduce the tension in the transmission belt forall operating conditions/situations, than 1 second can be used as the“set time duration” for that adjuster, or if desired further experimentscan be performed in order to obtain a smaller “set time duration”; andif 1 second does not allow the adjuster to sufficiently reduce thetension in the transmission belt for all driving conditions, thanadditional experiment(s) with larger than 1 second “set timeduration(s)” need to be performed until a “set time duration” thatallows the adjuster to sufficiently reduce the tension in thetransmission belt for all driving conditions is obtained.

When the “set time duration” has expired, axial position changing ofsaid cone can be started. After the “set time duration” has expired, theadjuster 8 stops providing/allowing a releasing torque and isstopped/locked or used for other purposes. Here proper coordination canbe performed by a controlling computer that controls the axial positionchanging of said cone, and the adjuster 8 that provides/allows thereleasing torque. Instead of a “set time duration”, torque sensor(s) canalso be used to determine when the tension in a transmission belt issufficiently reduced so that axial position changing of a cone can bestarted.

When providing/allowing a releasing torque, an adjuster 8 that uses amotor can eventually stall or slip. Here it is recommended that thetorque of the adjuster 8 motor is limited so that it will be enough torelease the tension in the pulling side of the transmission belt of itscone, but not large enough to significantly increase the tension in theslack side of the transmission belt.

For an adjuster that uses a motor that rotates a worm gear that iscoupled to a gear, letting an adjuster slip can be accomplished byplacing a slipping clutch between the output shaft/spline of theadjuster and the worm gear. This way the locking ability of the wormgear-gear drive is not compromised. See U.S. Pat. No. 7,722,490 B2 formore details regarding this.

If no slippage between a cone and its transmission belt is allowed, thenchanging the axial position of a cone relative to its transmission beltcan rotate a cone. This type of rotation is referred to as “Transmissionratio change rotation” in U.S. Pat. No. 7,722,490 B2. “Transmissionratio change rotation” has to be “allowed” or “compensated for” duringaxial position change of a cone relative to its transmission belt,otherwise large tension in the transmission belt can develop.

Furthermore, for a worm gear-gear drive of an adjuster 8, it isrecommended that the difference between the worm locking force and wormrotating force is not much greater than the difference required toensure reliable locking when needed. This way the torque required tounlock the worm gear-gear drive can be kept as small as practical.

If desired other type of adjusters can be used for the adjusters 8, suchas an adjuster that uses a worm gear-gear drive that uses a worm gearbrake so that its worm gear-gear drive can be made locking ornon-locking. Or an adjuster that uses a main gear that is identical tothe gear of a worm gear-gear drive that is than coupled directly orthrough other spur gears to a braking gear (which has more speed butless torque than said main gear) that can be braked as needed. Manyother design for an adjuster 8 are also possible.

Compensating/Allowing for “Transmission Ratio Change Rotation” in a CVT6

For a CVT 6 the cones are prevented from freely rotating to compensatefor “Transmission ratio change rotation”, since two cones that cannotfreely rotate relative to each other are mounted on a commonshaft/spline and the transmission ratio (axial position of a conerelative to its transmission belt) of the cones on said common splineare changed independent of each other. As such the adjuster(s) 8 alsoneed to be used to compensate/allow for “Transmission ratio changerotation”.

For a cone mounted on an adjuster 8, in order to compensate/allow for“Transmission ratio change rotation” of said cone, said cone mounted onan adjuster 8 “needs to be rotated” or “needs to be allowed to rotate”by its adjuster 8 in the direction of the “Transmission ratio changerotation” of said cone during axial position change of said conerelative to its transmission belt, so that said cone can rotate relativeto its spline in the direction of its “Transmission ratio changerotation”. For an adjuster 8 that uses a motor, it is recommended thathere said adjuster 8 rotates its said cone faster than required; theexcess speed of said adjuster 8 will only cause said adjuster 8 to stallor slip.

For a non-adjuster mounted cone, in order to compensate/allow for“Transmission ratio change rotation” of said non-adjuster mounted cone,the adjuster mounted cone to which said non-adjuster mounted cone iscoupled and which is mounted on an adjuster 8, “needs to be rotated” or“needs to be allowed to rotate” by adjuster 8 in the direction oppositeof the direction of rotation of the “Transmission ratio change rotation”of said non-adjuster mounted cone during axial position change of saidnon-adjuster mounted cone relative to its transmission belt. This isperformed so as to provide or remove slack as needed in the tense sideand slack side of the transmission belt of said non-adjuster mountedcone so as to compensate for “Transmission ratio change rotation”. Foran adjuster 8 that uses a motor, it is recommended that here saidadjuster 8 rotates its said cone faster than required; the excess speedof said adjuster 8 will only cause said adjuster 8 to stall or slip.

The explanations of the previous two paragraphs should be correct. Inorder to be entirely sure this is the case, or in order to determine thecorrect direction(s) of rotation if this is not the case,experimentation can be performed. There are only two possible directionsof rotation, so the experiments will be very simple.

When an adjuster 8 is used to compensate/allow for of “Transmissionratio change rotation”, it is recommended that the adjuster 8 starts toprovide/allow rotational adjustment slightly before rotationaladjustment to compensate/allow for of “Transmission ratio changerotation” is required. Since it is better to have the adjuster 8unlocked to compensate/allow for of “Transmission ratio change rotation”earlier, than later (where uncompensated “Transmission ratio changerotation” can cause large stresses in the transmission belt and preventa cone from moving axially).

The direction of “Transmission ratio change rotation” of a cone candepend on the configuration of the CVT 4's of the CVT 6, the axialmovement of said cone (“increasing transmission diameter change of saidcone” or “decreasing transmission diameter change of said cone”), andthe rotational position of said cone. Here the direction of“Transmission ratio change rotation” of a cone for all possible casescan be easily determined through experimentation (there are only twopossible directions for all cases).

An experiment to determine the direction of “Transmission ratio changerotation” of the cone(s) of a CVT 6 can be made by using a Test CVT. ATest CVT can be a CVT 6 for which the cones are mounted so that they caneach be set to either “freely rotate relative to the shaft/spline onwhich they are mounted” or “locked relative to the shaft/spline on whichthey are mounted”. Here “Transmission ratio change rotation” of a conefor a given axial movement and a given rotational position can be easilybe observed by first allowing said cone to “freely rotate relative tothe shaft/spline on which it is mounted” while keeping all other cones“locked relative to the shaft/spline on which they are mounted”, andthen changing the axial position of said cone and observing the rotationdue to it. By using this procedure repeatedly, the “Transmission ratiochange rotation” for all axial movements and all rotational positions ofa cone can be determined for all cones.

In some instances, the direction of rotation of “Transmission ratiochange rotation” of a cone depends on the rotational position of saidcone relative to its transmission belt. If so, this depends on where theneutral point (referred to as Point N) is positioned relative to thePoint M of its cone. Point N is the contact point between a cone and itstransmission belt that doesn't substantially rotate/move due to changesin the transmission diameter of said cone. Point M of a cone is thepoint were no rotational sliding between said cone and its torquetransmitting member occur due to axial position change of said torquetransmitting member relative to said cone. See U.S. Pat. No. 7,722,490B2 for detailed explanation regarding this.

Here experimentation using the Test CVT of the previous paragraph can beused to determine the direction of rotation of “Transmission ratiochange rotation” of a cone for the different relative rotationalpositions of said cone, such as “Point N positioned behind Point M”, andPoint N positioned ahead of Point M″.

If the direction of rotation of “Transmission ratio change rotation” ofa cone depends on the rotational position of said cone relative to itstransmission belt and only one adjuster 8 is used to compensate for“Transmission ratio change rotation”, then the duration at which theaxial position of a cone can be changed needs to be shorten so that itis not longer than the longest duration at which the direction ofrotation of “Transmission ratio change rotation” of said cone is in onedirection.

If two adjusters 8 are used to compensate for “Transmission ratio changerotation” of a cone, the axial position of said cone can be changedduring an interval where changes in the direction of rotation of“Transmission ratio change rotation” of said cone occur.

One method to allow axial position change of a cone during an intervalwhere changes in the direction of rotation of “Transmission ratio changerotation” of said cone occur, is by using motorized adjusters 8 andhaving both adjusters 8 of the cones that are mounted on the samespline/shaft rotate in the same direction (preferably faster thanrequired) during axial position change of one of said cones or a cone towhich said cones are coupled. This allows/compensates for clockwise andcounter-clockwise “Transmission ratio change rotation” of the cone whichaxial position is changed, since here one adjusters 8 allows/compensatesfor “Transmission ratio change rotation” in one direction and the otheradjusters 8 allows/compensates for “Transmission ratio change rotation”in the other direction. The torque of the adjusters 8 should be limitedso that they can only allow “Transmission ratio change rotation” in thedirection they are rotating. In order to ensure that the tension in thetransmission belt of the cone which axial position is changed remainslow, the adjuster 8 of the cone used for torque transmission shouldrotate the opposite direction of a releasing torque (a releasing torqueis a torque that releases the tension in its transmission belt). Thismethod is referred to as the “Active adjusters on the same shaftmethod”.

Another method to allow axial position change of a cone during aninterval where changes in the direction of rotation of “Transmissionratio change rotation” of said cone occur, is by using a configurationof a CVT 6 where all cones are mounted on an adjuster (see FIG. 8), andfor the CVT 4 for which the axial position of a cone is changed, havingthe adjusters 8 of the cone on the input shaft/spline and the adjuster 8of the cone on the output shaft/spline rotate in the same directionduring axial position change of said cone. Here one adjusters 8allows/compensates for “Transmission ratio change rotation” in onedirection and the other adjusters 8 allows/compensates for “Transmissionratio change rotation” in the other direction. The torque of theadjusters 8 should be limited so that they only allow “Transmissionratio change rotation” in the direction they are rotating. For thismethod the direction of rotation of the adjusters 8 (besides rotating inopposite directions) should be in the direction such that at least onecone of the CVT 4 for which the axial position of a cone is changed isrotated in the direction “the cone needs to rotate” or “the cone willneed to rotate after its axial position is changed” due to having conesof different diameters mounted on the same shaft/spline; here theadjusters 8 can simply stall or slip when their rotation are not needed.This method is referred to as the “Active adjusters on the same CVTmethod”.

It can be possible that the end of a torque transmitting member of acone that has just disengaged its transmission belt, re-engages with itstransmission belt because of “Transmission ratio change rotation”. Inorder to avoid this, for situations where applicable, axial positionchanging of a cone should be started after a cone has rotatedsufficiently past from “the position where the end of its torquetransmitting member has disengaged its transmission belt” in a mannersuch that re-engagement of said end with said transmission belt due to“Transmission ratio change rotation” will not occur.

For the “Active adjusters on the same shaft method”, under certainsituations (such as low speed and high torque situations), the tensionin the transmission belt for which the tension was reduced and for whichthe axial position of its cone(s) is changed, can significantly increasedue to “Transmission ratio change rotation”. Unless it can be ensurethat this is not happening under all operating conditions of the CVT 6,the “Active adjusters on the same CVT method” is preferred over the“Active adjusters on the same shaft method”, since otherwise there is noadvantage in reducing the tension in a transmission belt. Unlike the“Active adjusters on the same shaft method”, for the “Active adjusterson the same CVT method” no rotation of the input shaft/spline or outputshaft/spline in order to compensate for “Transmission ratio changerotation” is required, since the compensating rotations of the adjusters8 relative to their shafts/splines are sufficient. When rotation of theinput shaft/spline or output shaft/spline in order to compensate for“Transmission ratio change rotation” is required, large resistance torotation of the input shaft/spline or the output shaft/spline cansignificantly increase the tension in the transmission belt whichtension was reduced.

The required and torque and speed of an adjuster 8 can easily beobtained through trial-and-error and experimentation. “Transmissionratio change rotation” can be attributed to: a) “belt curvature changerotation”, which is rotation due to longitudinal movements of the slackside and/or tense side of a transmission belt relative to its cone inorder to provide/remove slack due to changes in the transmissiondiameter of its cone; and b) “member curvature change rotation”, whichis rotation due to changes in the curvature of the torque transmittingmember of the cone which axial position is changed.

If the axial position of a cone is changed so that the transmissioncircumference of its cone increases or decreases by an arc length of onefull tooth for all axial position changing steps, then the maximum “beltcurvature change rotation” for all axial position changing steps is onefull tooth and the maximum “member curvature change rotation” for allaxial position changing steps is also one full tooth. As such themaximum “Transmission ratio change rotation”, which is due to “beltcurvature change rotation” and “member curvature change rotation” is twoteeth.

The angular distance of two teeth depends on the total amount of teethwidth of the transmission circumference. If the transmissioncircumference of a cone is 20 teeth, then the angular distance of twoteeth is 2/20 times 360 deg. This angular distance has to be coveredduring the axial position changing interval of said cone. From thistheory, a ball park estimate for the required rotational speed andangular acceleration of the adjusters 8 for the most demanding operatingcondition (which should occur when the axial position changing intervalduration of a cone is shortest and the transmission circumference of acone is smallest) of the CVT 6 can be obtained. This ball park estimateand trial-and-error experimentation can then be used to obtain theactual minimum required rotational speed and angular acceleration of theadjusters 8 that allows for axial position change of all cones withoutinterruption due to “Transmission ratio change rotation” for alloperating conditions of the CVT 6.

“Transmission ratio change rotation” due to “belt curvature changerotation” in the slack side portion of the transmission belt can also becompensated by having the tensioning pulley/support pulley on the slackside of the transmission belt provide and remove slack in the slack sideof the transmission belt as needed in order to compensate for“Transmission ratio change rotation” due to “belt curvature changerotation” in the slack side of the transmission belt. A tensioningpulley/support pulley on the slack side of the transmission belt isshown in FIG. 6 where it is labeled as Tensioning Pulley 13.

If a tensioning pulley/support pulley on the slack side of thetransmission belt is used to compensate for “Transmission ratio changerotation” due to “belt curvature change rotation” in the slack side ofthe transmission belt (by providing an removing slack in the slack sideas necessary), then the adjusters 8 of a CVT 4 do not need to provideand remove slack in the slack side of the transmission belt tocompensate for “Transmission ratio change rotation” due to “beltcurvature change rotation” in the slack side of the transmission belt;so that both adjusters 8 of the CVT 4 can be rotated in the directionsthat increase slack in the tense side of the transmission belt ifallowed by “Transmission ratio change rotation due to “member curvaturechange rotation” or if “Transmission ratio change rotation due to“member curvature change rotation” is compensated/allowed using othermeans. Here slack that needs to be removed from the tense side of thetransmission belt can be compensated by the rotation of the driven cone,which rotates the slack from the tense side to the slack side.

A tensioning pulley/support pulley on the tense side of the transmissionbelt that provides and removes slack in the tense side of thetransmission belt as needed in order to compensate for “Transmissionratio change rotation” “due to “belt curvature change rotation” in thetense side of the transmission belt can also be used. The termtensioning pulley/support pulley is used to specify that the pulley isused for “tensioning its transmission belt” and for “supporting theshape of its transmission belt in manner as to ensure that a portion ofa torque transmitting member of its cone is always engaged with itstransmission belt”.

Unlike the slack side tensioning pulley/support pulley which needs toprovide and remove slack during all operating conditions, the tense sidetensioning pulley/support pulley can be designed so that it onlyprovides and removes slack when the tension in its transmission belt hasbeen reduced. As such, here a maximum contraction stop, which engageswith the tense side tensioning pulley/support pulley and stops themovement of the tense side tensioning pulley/support pulley when thetension in the transmission belt is not reduced, can be used. Here oncethe tension in the transmission belt has been reduced, the tense sidetensioning pulley/support pulley is pushed away from its maximumcontraction stop by its tensioning force, which can be provided byspring(s), weight(s), etcetera; and this should give the tense sidetensioning pulley/support pulley a “contracting and extending movementsrange” that can be used to provide and remove slack when required. Herethe contracting movements range allow the tense side tensioningpulley/support pulley to move away from its transmission belt, and theextending movements range allow the tense side tensioning pulley/supportpulley to move towards from its transmission belt.

A front-view of a CVT 4 that uses slack side tensioning pulley/supportpulley and a tense side tensioning pulley/support pulley is shown inFIG. 6. In FIG. 6, the slack side tensioning pulley/support pulley islabeled tensioning pulley 13, and the tense side tensioningpulley/support pulley is labeled tensioning pulley 14. Tensioning pulley14 is also shown in FIG. 7. In FIG. 6, tensioning pulley 14 is engagedwith its maximum contraction stop 15 since the tension in itstransmission belt has not been reduced. In FIG. 7, tensioning pulley 14is not engaged with its maximum contraction stop 15 since the tension inits transmission belt has been reduced.

Also shown in FIG. 7 are the up and down directions of the contractingand extending movements of tensioning pulley 14; tensioning pulley 13can have the same directions. If desired other directions of thecontracting and extending movements of the tensioning pulleys can beused, such as diagonally for example, since the directions of thecontracting and extending movements of the tensioning pulleys can be anydirections that can remove and provide transmission belt slack.

It is also recommended that the slack side tensioning pulley/supportpulley (labeled as tensioning pulley 13 in FIG. 6 also has a maximumcontraction stop 15. Here the maximum contraction stop can be used toprevent excessive contracting movement of the slack side tensioningpulley/support pulley due to increase in tension in the slack side ofits transmission belt, which can be due to a releasing torque provide byits adjuster(s) 8 or due to rotations of its cone(s) due to having tocompensate for having cones of different diameters mounted on the sameshaft/spline.

If both a slack side tensioning pulley/support pulley and a tense sidetensioning pulley/support pulley are used, then the contracting andextending movements of the pulleys can “compensate for Transmissionratio change rotation” and can “compensate for having cones of differentdiameters mounted on the same shaft/spline during axial positionchanging of a cone”; in addition to “accommodating for the transmissiondiameter change of a cone”. If the transmission belts of a CVT 6 areremoved, then “changing the axial position of a cone of a shaft/splinewhile not changing the axial position of the other cone of thatshaft/spline” or “having cones with different transmission diametersmounted on a common shaft/spline” is not a problem. This is because“changing the axial position of a cone of a shaft/spline while notchanging the axial position of the other cone of that shaft/spline” or“having cones with different transmission diameters mounted on a commonshaft/spline” is only a problem if the transmission belts of a CVT 6 arenot removed and either or both the tense sides or slack sides of thetransmission belts are of a fixed length, since you cannot have twodifferent CVT's constrained to a common input shaft/spline and outputshaft/spline. Besides removing the transmission belts, having the slackside tensioning pulley/support pulley and the tense side tensioningpulley/support pulley provide and remove slack as needed also removesthe constrains imposed by the transmission belts.

If both a slack side tensioning pulley/support pulley and a tense sidetensioning pulley/support pulley are used, the tensioning forces of thepulleys should be balanced such that when the tension in thetransmission belt has been reduced, both pulleys are positioned so thatthey have a sufficient “contracting and extending movement range” toprovide and remove slack as needed to “compensate for Transmission ratiochange rotation”, to “accommodate for the transmission diameter changeof a cone”, “to compensate for having cones of different diametersmounted on the same shaft/spline during axial position changing of acone”, and by compensating for any other rotations/needs that mightoccur during axial position changing of their cone.

Here it is preferred that the tensioning forces of the pulleys areprovided by springs, since here slightly unbalanced tensioning forces ofthe pulleys can be balanced/equaled by slight movements of the pulleys.The required “contracting and extending movement ranges” of the pulleyscan be obtained through “trial and error” experimentation; as aconservative estimate that can be refined through “trial and error”experimentation, a movement range that allows for 3 teeth rotation of acone in both directions can be used. Also here the axial position of acone should only be changed after the slack side tensioningpulley/support pulley and the tense side tensioning pulley/supportpulley have reached their balanced positions.

For the preferred CVT 6, the axial positions of the cones of a CVT 6 arechanged in manner such that when there are “cones with differenttransmission diameters mounted on a same shaft/spline”, the next axialposition change of a cone is always such that the transmission diametersof said “cones with different transmission diameters mounted on a sameshaft/spline” are equal. Therefore, since during regular operations(non-“transmission ratio changing” operations) of a preferred CVT 6 thetransmission diameters of all cones mounted on the same shaft/spline areequal, there should be only one shaft/spline at a time for which thereare “cones with different transmission diameters mounted on a sameshaft/spline”.

During axial position changing of a cone of the preferred CVT 6, whenthere are no “cones with different transmission diameters mounted on thesame shaft/spline”, before or immediately after the axial position of acone (referred to as the moved cone) is/has been changed, one adjuster 8of a cone (referred to as the rotated cone) needs to “rotate preferablyfaster than required” or “have its worm gear-gear drive unlocked” in thedirection “the rotated cone will need to rotate in order to “compensatefor having cones with different transmission diameters mounted on a sameshaft/spline” after the axial position of the moved cone is changed”.

Here if a motorized adjuster 8 is used, then the adjuster 8 can be usedto rotate its cone before the axial position of a cone is changed; sincethis type of adjusters 8 only allows rotation in one direction and herethe adjuster 8 can simply stall, slip, or stop when its rotation is“not” or “not yet” needed. If a non-motorized adjuster 8 is used and therotated cone is not a cone of the “CVT 4 which transmission belt tensionhas been reduced”, then it is recommended that the adjuster 8 is onlyunlocked immediately after the axial position of a cone has beenchanged, so that it does not rotate in the direction that reduces thetension in its transmission belt.

Also here the rotated cone is only “rotated” or “allowed to rotate” inthe direction that increases the tension in the tense side of itstransmission belt; the selection of whether the rotated cone is a conethat is coupled to the transmission belt which tension was reduced, or acone that is coupled to the transmission belt which tension was notreduced should depend only on this. Since here if the rotated cone is acone of the “CVT 4 which transmission belt tension has been reduced”,then after the axial position of the moved cone, the tension in thetransmission belt of the “CVT 4 with which the CVT 4 of the rotated coneis alternately used to transfer torque” can be reduced by using one ofits adjuster 8 to rotate one of its cone in the direction needed to“compensate for having cones with different transmission diametersmounted on the same shaft” (which is also the direction of rotation fora releasing torque for the “CVT 4 with which the CVT 4 of the rotatedcone is alternately used to transfer torque”), so that said rotated conecan be slowed-down and eventually locked by its adjuster 8. Thisprevents having adjusters 8 of both CVT 4's become unlocked, which isundesirable since relocking an adjuster 8 under load can require a largetorque. And since here if the rotated cone is a cone of the “CVT 4 whichtransmission belt tension is not reduced”, then after the axial positionof the moved cone, the transmission belt tension in said “CVT 4 whichtransmission belt tension is not reduced” becomes reduced; this isbecause its adjuster 8 is rotating in the direction that increases thetension in its transmission belt in order to prevent an increase intransmission belt tension in the other CVT 4 and the torque of anadjuster 8 should not be large enough such that it can increase thetransmission belt tension in its CVT 4. Also here the moved cone and therotated cone can be or cannot be the same cone, depending on thesituation.

According to the previous paragraph, during axial position changing of acone of the preferred CVT 6, when there are no “cones with differenttransmission diameters mounted on the same shaft/spline”, before orimmediately after axial position changing of a cone and until relived byan adjuster 8 of the other CVT 4 or until its rotation is not neededanymore due to a subsequent “axial position changing of a cone” thatequalize the transmission diameters of all cones mounted on the sameshaft, the direction that an adjuster 8 “rotates” or “allows to rotate”its cone in order to “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline after the axialposition of the moved cone is changed” is in the direction thatincreases the tension in the tense side of its transmission belt. Herefor two cones mounted on a common input shaft/spline, the smaller coneneeds to be “rotated” or “allowed to rotate” by its adjuster 8 in thedirection said common input shaft/spline is rotating; or a cone that ismounted on an output shaft/spline and that is coupled to said smallercone, needs to be “rotated” or “allowed to rotate” in the oppositedirection said output shaft/spline is rotating (here the transmissiondiameters of the cones mounted said output shaft/spline should beidentical). And here for two cones mounted on a common outputshaft/spline, the larger cone needs to be “rotated” or “allowed torotate” by its adjuster 8 in the opposite direction said common outputshaft/spline is rotating; or a cone that is mounted on an inputshaft/spline and that is coupled to said larger cone, needs to be“rotated” or “allowed to rotate” in the direction said inputshaft/spline is rotating (here the transmission diameters of the conesmounted said input shaft/spline should be identical).

During axial position changing of a cone of the preferred CVT 6, whenthere are “cones with different transmission diameters mounted on thesame shaft/spline”, before and during axial position changing of a cone,the cone that is used to “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline” should be rotatedby its adjuster 8 in the direction required (see previous two paragraphsand the paragraph below). Here after the axial position changing of acone, the transmission diameters of all cones mounted on a sameshaft/spline should be equal so that there is no need to have anadjuster 8 “compensate for having cones with different transmissiondiameters mounted on a same shaft/spline”; so that the active/unlockedadjuster 8 can simply be stopped/braked/“locked when possible”.

Regarding the previous paragraph, during axial position changing of acone of the preferred CVT 6, when there are “cones with differenttransmission diameters mounted on the same shaft/spline” due to a firstaxial position changing of a cone (see previous 4 paragraphs), theneither: a) in order to the release tension in the transmission belt ofthe “CVT 4 for which the axial position of a cone is to be changed” andto “compensate for having cones with different transmission diametersmounted on a same shaft/spline”, a larger cone of said CVT 4 that ismounted on the input shaft/spline should be rotated in the oppositedirection said input shaft/spline is rotating by its adjuster 8; orsmaller cone of said CVT 4 that is mounted on the output shaft/splineshould be rotated in the direction said output shaft/spline is rotatingby its adjuster 8. Or b) in order to maintain the released tension inthe transmission belt of the “CVT 4 for which the axial position of acone is to be changed” and to “compensate for having cones withdifferent transmission diameters mounted on a same shaft/spline”, asmaller cone of said CVT 4 that is mounted on the input shaft/splineshould be rotated in the direction said input shaft/spline is rotating;or larger cone of said CVT 4 that is mounted on the output shaft/splineshould be rotated in the opposite direction said output shaft/spline isrotating.

During axial position changing of a cone, in order to prevent anincrease in tension in the transmission belt for which the tension wasreduced (which should be the transmission belt of the cone which axialposition is to be changed) due to changes in the transmission diameterof the cone which axial position is changed (which occurs when thetransmission diameter for a cone mounted on the input shaft/spline isincreased, or when the transmission diameter for a cone mounted on theoutput shaft/spline is decreased), the contracting and extendingmovements of the slack side tensioning pulley/support pulley and thetense side tensioning pulley/support pulley should be able to“compensate for having cones with different transmission diametersmounted on a same shaft/spline” during axial position changing of acone. Here it is not required that only the contracting and extendingmovements of the tensioning pulleys are used to “compensate for havingcones with different transmission diameters mounted on a sameshaft/spline” during axial position changing of a cone; however, here itis required that the ability of the contracting and extending movementsof the tensioning pulleys to “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline” has not beenexhausted during axial position changing of a cone. When the axialpositions of a cone is changed such that its circumference is increasedor decreased by one tooth during an axial position changing interval;then during one full rotation of the cone, the maximum amount ofrotation needed to compensate for having cones with differenttransmission diameters mounted on a same shaft/spline is “one tooth” or“slightly more than one tooth”, so this should be feasible.

The tension in the transmission belt of a “CVT 4 for which thetransmission belt tension was reduced” can be increased by rotating acone of the other CVT 4 in the direction that reduces its transmissionbelt tension, and if necessary slowing-down and eventually locking allcones of said “CVT 4 for which the transmission belt tension wasreduced”. Since increasing the tension in the transmission belt of oneCVT 4 reduces the tension in the transmission belt of the other CVT 4.For example, for an input shaft/spline on which a smaller cone (smallertransmission diameter cone) and larger cone (larger transmissiondiameter cone) are mounted; when said smaller cone is currently rotatedby its adjuster 8 in the direction said input shaft/spline is rotatingin order “compensate for having cones with different transmissiondiameters mounted on a same shaft/spline”, then “the tension of thetransmission belt of said larger cone can be reduced and the tension ofthe transmission belt of said smaller cone can be increased” by rotatingsaid larger cone in the opposite direction said input shaft/spline isrotating in order “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline” and slowing-downand eventually locking the adjuster 8 of said smaller cone.

Changing the axial position of a cone can also increase the tension inthe transmission belt for which the tension is reduced when no adjuster8 of the CVT for which the transmission belt tension is reduced isactive or unlocked. Examples of this is when the transmission diameterof a cone mounted on the input shaft/spline is increased and the slackthat can be provided by its tense side tensioning pulley/support pulleyhas been exhausted; and when the transmission diameter of a cone mountedon the output shaft/spline is decreased and slack that can be providedby its tense side tensioning pulley/support pulley has been exhausted.It is recommended that this only occurs after the axial position of acone has been changed, since otherwise there might be little benefit inreducing the tension in a transmission belt in order to reduce the forceneeded to change the axial position of a cone.

By using a slack side tensioning pulley/support pulley and a tense sidetensioning pulley/support pulley to allow/compensate for “Transmissionratio change rotation”, the need to accurately determine thedirection(s) of “Transmission ratio change rotation” becomesunnecessary.

Preferred Transmission Ratio Changing Procedure for a CVT 6

In this section, the “preferred transmission ratio changing procedurefor a CVT 6” that can be used to reduce the torque requirements of theadjusters (adjusters 8) of a preferred CVT 6 is described. Using the“preferred transmission ratio changing procedure for a CVT 6”, thetorque requirements of the adjuster motors can be reduced to a levelwhere the adjuster motors only need sufficient torque to unlock theirworm gear-gear drives (the worm gear-gear drives of their adjusters)when needed and sufficient torque (braking torque if necessary) torelock their worm gear-gear drives when they are “slowing-down and aboutto change their direction of rotation”. Here during relocking, theadjuster motors are assisted by the “static locking friction” of theirworm gear-gear drives, and during unlocking the adjuster motors need toovercome the “static locking friction” of their worm gear-gear drives.

An adjuster is mounted on a shaft/spline and is used to controllablylock and unlock a cone mounted on it. When an adjuster is locked, itdoes not allow relative rotation between its cone and the shaft/splineon which it is mounted; and when an adjuster is unlocked, it allowsrelative rotation between its cone and the shaft/spline on which it ismounted.

An example of an adjuster is an adjuster that comprises of a housingthat can be mounted on a shaft/spline in a manner so that it is fixedfor rotation relative to said shaft/spline. Attached to said housing area worm gear, an adjuster motor that can rotate said worm gear directlyor through means for coupling (coupling gears, etc.), and a gear thatengages with said worm gear. When said worm gear is rotating, said gearrotates relative to said housing. Attached to said gear is an outputshat that is used to attach the cone of the adjuster, in a manner sothat the rotation of said gear can be used to rotate said cone relativeto its shaft/spline. Also, an adjuster motor should also be able torotate at a sufficient speed to keep its worm gear-gear drive unlocked.See the “Adjusters for a CVT 6” section for additional details for anadjuster.

An unlocked adjuster should allow rotation at the speed required evenwhen the “speed its adjuster motor rotates its adjuster outputshaft/spline” is less than the “speed applied on its adjuster outputshaft/spline (such as due to transmission ratio change rotation, havingcones of with different diameters mounted on the same shaft/spline,etc.)”. Based on worm gear theory, here the worm gear-gear drive shouldbe selected such that: a) the static friction of the worm gear-geardrive is large enough to have the worm gear-gear drive be self-locking;and b) the dynamic (rotating) friction of the worm gear-gear drive isnot be large enough to have the worm gear-gear drive be self-locking. Orwhen the adjuster motor of an adjuster is always ON when an adjuster isunlocked, the worm gear-gear drive can also be selected such that: a)the static friction of the worm gear-gear drive is large enough to havethe worm gear-gear drive be self-locking; and b) the dynamic friction ofthe worm gear-gear drive at “the rotating speed of the worm gear as canbe provided by the adjuster motor” is not be large enough to have theworm gear-gear drive be self-locking (here the dynamic friction of theworm gear-gear drive at a rotating speed of the worm gear that is slowerthan “the rotating speed of the worm gear as can be provided by theadjuster motor” can still be self-locking; but at speeds “equal to andhigher” than “the rotating speed of the worm gear as can be provided bythe adjuster motor”, the worm gear-gear drive should not beself-locking).

What static coefficient of friction of the worm gear-gear drive allowsfor reliable locking of an adjuster can easily be determined throughsimple experimentation.

Once an adjuster is released when it needs to be released, the adjustermotor should be operated so that it will not add resistance that willstop the released adjuster from being released, as can occur insituations where the cone of an adjuster needs to rotate at a higherspeed than the speed that can be supplied by its adjuster motor(released means being able to rotate at any speed required). As such itis recommended that here the adjuster motor is operated so as to provideas little rotating resistance as possible when its speed is slower thanthe speed of its cone. If a brushed electric motor is used as theadjuster motor, it might be desirable to leave it ON, since theswitching of the poles are controlled by the rotation of the rotor. Andif a brushless electric motor is used as the adjuster motor, it might bedesirable to turn it off, since the switching of the poles arecontrolled by an electric motor controller and not the rotation of therotor. Experimentation or somebody skilled in the art should be able todetermine how to operate an electric motor with as little rotatingresistance as possible.

If it is desirable, a rotation sensor or a rotational speed sensor thatmeasures the rotation or rotational speed of the worm gear can be usedto turn an electric motor off “once an adjuster is released” or “once anadjuster is released and once the worm gear has reached a pre-set rpmspeed”.

The adjuster motor of an adjuster should be selected so that it can berotated at the necessary speed required (without overheating or otherdamages). If a shaft/spline of a cone rotates at 3000 rpm, and thetransmission diameter of one cone is equal to 30 teeth and thetransmission diameter of other cone is equal to 31 teeth, then the speedone cone has to be rotated relative to the other is,V_cone=[(31−30)/30]*3000=100 rpm. If the worm gear-gear drive has a 25:1gear ratio, then the adjuster motor has to be able to be rotated at,V_adjuster motor=100 rpm*25/1=2500 rpm. Simple experimentation can beused if this is incorrect.

When an unlocked adjuster is slowed down in order to be eventuallystopped/locked (see below for details), its adjuster motor should bestopped, made to rotate in the opposite direction of the direction it iscurrently rotating, or made to apply a braking torque until the adjusteris locked.

When an adjuster is unlocked but “the speed its adjuster motor rotatesits adjuster output shaft” is less than “the speed applied on itsadjuster output shaft/spline”, then an increase in tension in the slackside or tense side of the transmission belt of its CVT 4 can occur; thisis due to the pulling tension required to rotate the unlocked adjusteroutput shaft. If this causes problems, the tension of the tensioningpulleys/support pulleys of its CVT 4 can be increased; or the speed ofits adjuster motor can be increased so that the “speed its adjustermotor rotates its adjuster output shaft” is equal to or more than the“speed applied on its adjuster output shaft”. Or, if desired an externalmotor (which avoids the speed reduction gearing of the worm gear-geardrive of the adjuster) can be used to rotate the cone of an adjuster asrequired.

Alternately an adjuster can also be designed so that the “kineticlocking friction force” of its worm gear-gear drive is never less thanthe rotational force applied to its adjuster output shaft. Since herethe adjuster will not allow free rotation at any speed required, itsadjuster motor needs to be able rotate its adjuster output shaft at thespeed required or faster for all operating conditions of its CVT.

Instead of using an adjuster motor to controllably lock and unlock anadjuster, a brake can be used. Here when an adjuster needs to be locked,the brake applies braking friction (directly or through means forcoupling such as gears, etc.) to the shaft of the worm gear of the wormgear-gear drive; and when an adjuster needs to be unlocked, the brakedoes not apply braking friction to the shaft of the worm gear of theworm gear-gear drive. If desired, a brake can also be used inconjunction with an adjuster motor to controllably lock and unlock anadjuster.

If a brake is used by itself, then the brake needs to be able to providesufficient braking that prevents a worm gear-gear drive from becomingunlocked for all regular operating conditions of its CVT. Here the wormgear-gear drive itself should not be self-locking, since it needs to beunlocked when the brake is released.

A brake can comprise of a braking disk that is coupled directly orthrough means for coupling to the shaft of the worm gear of the wormgear-gear drive, and a braking shoe that is pushed towards the brakingdisk by a spring and that can be controllably pulled away from thebraking disk by a solenoid.

When a brake is used with an adjuster motor; then the “locking(frictional) force of the worm gear-gear drive when the worm gear isstationary” can be equal, smaller, or larger than the “unlocking(rotating) force of the worm gear-gear drive when the worm gear isstationary”. Here the brake and the adjuster motor should be selected sothat they can lock and unlock their adjuster as needed for all regularoperating conditions of their CVT.

Instead of using an adjuster motor or brake to controllably lock andunlock an adjuster, an indexing mechanism that can be controllablylocked and unlocked can be used instead. The indexing mechanism cancomprise of an index wheel with cavities, which is coupled directly orthrough means for coupling to the shaft of the worm gear of the wormgear-gear drive, and a locking mechanism for controllably locking andunlocking the index wheel. Said locking mechanism can comprise of a lockthat can be inserted into a cavity of the index wheel, wherein said lockis pushed towards said index wheel by a spring and wherein said lock canbe controllably pulled out of an index wheel cavity by a solenoid. Herethe worm gear-gear drive of the adjuster should not be self-locking,since it needs to be unlocked when the indexing mechanism is unlocked.

If desired an indexing mechanism by itself, without a worm gear-geardrive can be used to controllably lock and unlock an adjuster. But forthis design, the force needed to unlock an adjuster are most likelylarger; and the shock-loads during relocking of an adjuster are alsomost likely larger. The indexing mechanism used here can comprise of anindex wheel with cavities that is coupled directly or through means forcoupling to the output shaft of its adjuster, which is the shaft that isfixed for rotation relative to the cone of said adjuster; and a lockingmechanism for controllably locking and unlocking the index wheel, whichis fixed for rotation relative to the spline/shaft of the cone of saidadjuster. Said locking mechanism can comprise of a lock that can beinserted into a cavity of the index wheel, wherein said lock is pushedtowards said index wheel by a spring and wherein said lock can becontrollably pulled out of an index wheel cavity by a solenoid.

The function of an adjuster of a cone is to either “lock the rotationalposition of said cone relative to its spline/shaft” or “unlock said conefor rotation in the direction it is being pulled by its transmissionbelt relative to its spline/shaft”. As such, the process of using anadjuster that uses an adjuster motor, a brake, or an indexing mechanismare basically identical. But, while an adjuster that uses an adjustermotor can lock itself once the speed of its worm gear has reduced to aspeed where the friction of the worm gear-gear drive has sufficientlyincreased, an adjuster that uses a brake or an indexing mechanism has tobe controllably locked. An adjuster should only be controllably lockedonce “the rotation it allows” is not needed anymore.

A preferred CVT 6 (a CVT 6 is a CVT that uses two substantiallyidentical CVT 4's, see FIGS. 5 and 9 for examples) is a CVT 6 that usesone adjuster for each CVT 4 (it doesn't matter on which shaft/spline oftheir CVT 4 the adjusters are mounted); and a CVT 6 for which each CVT 4has both a slack side tensioning pulley/support pulley and a tense sidetensioning pulley/support pulley (see FIG. 6). The slack side tensioningpulleys/support pulleys and the tense side tensioning pulleys/supportpulleys have sufficient (preferably slightly more, to prevent exhaustionof their ability to provide and remove slack during axial positionchanging of a cone of their CVT) “contracting and extending movementranges” to provide and remove slack (slack throughout this disclosurerefers to transmission belt slack) needed to allow for axial positionchanging of a cone of their CVT for all operating conditions of theirCVT even when no adjuster is active, by “compensating for Transmissionratio change rotation, by “accommodating for the transmission diameterchange of a cone”, by “compensating for having cones of differenttransmission diameters mounted on the same shaft/spline”, and bycompensating for any other rotations/needs that might occur during axialposition changing of their cone.

Unlike a slack side tensioning pulley/support pulley (labeled as 13 inFIG. 6), which needs to be able to provide and remove slack during alloperating conditions of its CVT when needed, a tense side tensioningpulley/support pulley (labeled as 14 in FIG. 6) can be designed suchthat it can only provide and remove slack when the tension in itstransmission belt has been reduced. As such, here a maximum contractionstop (labeled as 15 in FIG. 6), which engages with the tense sidetensioning pulley/support pulley (labeled as 14 in FIG. 6) and stops themovement of the tense side tensioning pulley/support pulley when thetension in the transmission belt is not reduced, can be used. Here oncethe tension in the transmission belt has been reduced, the tense sidetensioning pulley/support pulley should be pushed away from its maximumcontraction stop by its tensioning force (as shown as in FIG. 7); andthis should give the tense side tensioning pulley/support pulley a“contracting and extending movements range” that can be used to provideand remove slack when required.

It is recommended that both the slack side tensioning pulley/supportpulley and the tense side tensioning pulley/support pulley have each a“maximum contraction stop”. The “maximum contraction stops” should beused to limit the movements of the tensioning pulleys/support pulleys toa range that allows for proper operation.

It is recommended that the tensioning forces of the tensioningpulleys/support pulleys are provided by compression springs, whichtensioning forces increase as they are compressed more. Since hereslightly unbalanced tensioning forces of the tensioning pulleys/supportpulleys can be balanced/equaled by slight movements of the tensioningpulleys/support pulleys. For example, after the tension in theirtransmission belt has been reduced, when the spring of the tense sidetensioning pulley/support pulley is more compressed than the spring ofthe slack side tensioning pulley/support pulley, then the largertensioning force of the spring of the tense side tensioningpulley/support pulley can reduce the compression in the spring of thetense side tensioning pulley/support pulley and increase the compressionin the spring of the slack side tensioning pulley/support pulley untilthe tensioning pulleys/support pulleys have reached their equilibriumposition. Using tensioning springs or other tensioners for which theirtransmission belt tensioning force increase as their “availablecontraction distance” is reduced can also be used. The “availablecontraction distance” of a tensioning pulley/support pulley is thedistance a tensioning pulley/support pulley can be moved towards its“maximum contraction stop” (see FIG. 6), and it determines the amount ofslack that can be provided by that tensioning pulley/support pulley whenneeded.

In general (there can be exceptions for steps d) and e) of the“preferred transmission ratio changing procedure for a CVT 6” shownbelow if desired), the stiffness of the tensioners of the tensioningpulleys/support pulleys, the ranges of the tensioning pulleys/supportpulleys, and the parameters (torque, speed, unlocked frictionalresistance, etc.) of the adjusters should be selected so that when thetension in their transmission belt has been reduced, the tense sidetensioning pulley/support pulley and the slack side tensioningpulley/support pulley each have a sufficient “contracting and extendingmovement range” to provide and remove slack as needed to allow for axialposition changing of a cone for all operating conditions of their CVTwithout excessively stretching a transmission belt, by “compensating forTransmission ratio change rotation”, by “accommodating for thetransmission diameter change of a cone”, by “compensating for havingcones of different transmission diameters mounted on the sameshaft/spline”, and by compensating for any other rotations/needs thatmight occur during axial position changing of their cone. This willensure that the tension in the “transmission belt which tension has beenreduced” will remain reduced during axial position changing of itscone(s). Since the transmission diameter of a cone is preferably onlychanged 1 tooth at a time, this should be feasible. Here when thetension in their transmission belt has been reduced, the tense sidetensioning pulley/support pulley and the slack side tensioningpulley/support pulley should each have a said sufficient “contractingand extending movement range” when their adjuster is unlocked,regardless of whether the adjuster is stalling, rotating and applying atorque on said transmission belt (in whatever direction required), orsimply unlocked; and when their adjuster is not unlocked Here simpletrial and error experimentation and/or engineering can be used.

In order to move vertically as required, the tensioning pulleys/supportpulleys can each be mounted on a spring loaded vertical slider. A springloaded vertical slider can comprise of a vertical slider that allows forsufficient vertical movements as required, and a spring that providessufficient tensioning forces as required. If the tensioningpulleys/support pulleys are also to be allowed to move horizontally, thespring loaded vertical sliders can each be mounted on a horizontalsliders; or the spring loaded vertical sliders can each have slottedholes into which the shafts of tensioning pulleys/support pulleys areinserted and fastened using bolts or locking rings, as partially shownin FIG. 6.

An example of a system that allows the tensioning pulleys/supportpulleys to move vertically as required is shown and described in the“Detailed Design for Tensioning Pulleys Tensioning System”. Besidessprings, the tensioning forces for the tensioning pulleys/supportpulleys can also be provided by elastomers, pneumatics/hydraulics (suchas through linear actuators for example), etc.

It is recommended that the tensioning forces of the tensioningpulleys/support pulleys are not be large enough so that theysignificantly increase the force required to change the axial positionof the cones of their CVT.

The “preferred transmission ratio changing procedure for a CVT 6” isdescribed in the paragraphs below.

a) Initial Setup/Non-Transmission Ratio Changing Operation Configuration

Before a transmission ratio changing procedure is started, thetransmission diameters of all cones mounted on a same shaft/spline (suchas the input shaft/spline and output shaft/spline) are equal; and theadjuster of at least one CVT 4 is locked. This should be theconfiguration of the CVT 6 during non-transmission ratio changingoperation.

b) Reducing Transmission Belt Tension

Next, if not already so, the tension in the transmission belt of “theCVT 4 for which the axial position of a cone is to be changed” isreduced. Here the adjuster for “the CVT 4 for which the axial positionof a cone is to be changed” is unlocked if not already so, while theadjuster of the other CVT 4 remains stopped/locked/braked so that fulltorque transfer between its cone and its shaft/spline occurs.

Here if an adjuster that uses an adjuster motor is used, then in orderto unlock the adjuster, the adjuster needs to rotate its cone relativeto its shaft/spline so as to provide a releasing torque. If theshaft/spline on which an adjuster is mounted is the input shaft/spline,then the direction of rotation of its cone for a releasing torque is thedirection opposite from the rotation of the input shaft/spline. And ifthe shaft/spline on which an adjuster is mounted is the outputshaft/spline, than the direction of rotation of its cone for a releasingtorque is the direction of rotation of the output shaft/spline.

And here if an adjuster that uses a brake is used, then in order tounlock the adjuster, its brake needs to be released; and if an adjusterthat uses an indexing mechanism is used, then in order to unlock theadjuster, its indexing mechanism needs to be unlocked.

Once the tension in the transmission belt of “the CVT 4 for which theaxial position of a cone is to be changed” has been sufficientlyreduced, which can be based on “a set time duration required to achievethis” (preferred) or “a torque sensor”, the adjuster used to reduce thetension in the transmission belt of “the CVT 4 for which the axialposition of a cone is to be changed” should be stopped/braked/locked ifit is not the adjuster of the rotated cone of the next step (“step c)First axial position changing of a cone”). But if the adjuster used toreduce the tension in the transmission belt of “the CVT 4 for which theaxial position of a cone is to be changed” is the adjuster of therotated cone of the next step, then it should be left unlocked.

If an indexing mechanism is used, then because of the incrementallooking steps of the indexing mechanism, here it might not be possibleto lock the adjuster (refer to the “Adjusters for a CVT 6” section fordetails) if needed (such as when it is not the adjuster of the rotatedcone); if so, the adjuster should be locked “before” or “immediatelyafter” axial position changing of a cone of the next step (“step c)First axial position changing of a cone”) has been completed.

Regarding locking of the adjuster used to reduce the tension in thetransmission belt of “the CVT 4 for which the axial position of a coneis to be changed”, if an adjuster that uses an indexing mechanism isused, then in order to be able to lock the adjuster, its cone needs torotate a sufficient amount relative to its shaft/spline so that the lockof the indexing mechanism can enter a circumferential cavity of itsindex wheel.

Here if it is desired to lock the adjuster used to reduce the tension inthe transmission belt of “the CVT 4 for which the axial position of acone is to be changed”, before “the slack that can be provided and/orremoved by the tensioning pulleys/support pulleys as needed” has beenexhausted (such as during and slightly after axial position changing ofa cone), then the “tension of the tensioning pulleys/support pulleys”and the “rotational frictional resistance of the worm gear-gear drive ofthe adjuster” should be selected such that an unlocked cone can rotate asufficient amount relative to its shaft/spline when rotating forces areapplied to that the cone even if “the slack that can be provided and/orremoved by the tensioning pulleys/support pulleys as needed” has notbeen exhausted.

And if it is acceptable to lock the adjuster used to reduce the tensionin the transmission belt of “the CVT 4 for which the axial position of acone is to be changed” after “the slack that can be provided and/orremoved by the tensioning pulleys/support pulleys as needed” has beenexhausted (such as slightly after axial position changing of a cone),then the “tension of the tensioning pulleys/support pulleys” can beselected independently from the “rotational frictional resistance of theworm gear-gear drive of the adjuster”. But here, unlike the set-up ofthe previous paragraph, the adjuster is locked while it is transmittingtorque; as such, if the set-up of the previous paragraph can be easilyachieved, it is recommended.

It is recommended that the index wheel of an adjuster is locked duringaxial position changing of a cone, otherwise it has to be locked afteraxial position changing of a cone has been completed.

As a ball park figure that can be refined through trial-and-errorexperimentation (and depending on the size of the lock and the size ofthe index wheel used), in order to be able to lock an adjuster duringaxial position changing of a cone, an unlocked index wheel of anadjuster should be able to get locked when its cone has rotated lessthan ¼ of a tooth width of said cone. For reliability purposes, it isdesirable to be able to lock an unlocked index wheel at an even smallerrotation of its cone.

In order to reduce the amount of rotation required to lock an unlockedindex wheel, a speed increasing gear train (such as a larger gearcoupled to a smaller gear for example) can be used to couple therotation of the worm to the index wheel. A speed increasing gear trainwill also reduce the torque at the index wheel, which is desirable.

Another approach to reduce the amount of rotation required to lock anunlocked index wheel is by using several index wheels that areconstrained relative to each other for rotation (such as by stackingseveral index wheels to common shaft) and that are rotationally offsetrelative to each other; wherein each index wheel has its own lock, alllocks are forced toward their index wheel at the same time, and only oneindex wheel is fully locked at any instance.

For reliability purposes, here in order to ensure that an adjuster isalways locked, it is preferred that a “wait/pause duration to ensure theadjuster is locked after axial position changing of a cone has beencompleted” is used.

c) First Axial Position Changing of a Cone

It is recommended that this step is initiated immediately after “Step b)Reducing transmission belt tension”, in order to avoid changes in the“contracting and extending movement ranges” of the “tensioningpulleys/support pulleys for which the tension in their transmission belthas been reduced” due to slight differences in the transmissiondiameters of the cones mounted on same shaft/spline or any otherfactors.

After the axial position changing of a cone of this step (“step c) Firstaxial position changing of a cone”) has been performed, there are twocones with different transmission diameters mounted on a sameshaft/spline. Here in order to prevent an excessive increase in tensionof a transmission belt, this has to be compensated by having at leastone adjuster of a CVT 4 unlocked. The cone of the adjuster that isunlocked to “compensate for having cones with different transmissiondiameters mounted on a same shaft/spline” is referred to as the rotatedcone.

If the “adjuster of the rotated cone” is the adjuster that is used toreduce the tension in the transmission belt of “the CVT 4 for which theaxial position of a cone is to be changed”, which was performed in theprevious step (“step b) Reducing transmission belt tension”), then theadjuster does not have to be locked after it was used to reduce thetension in the transmission belt of “the CVT 4 for which the axialposition of a cone is to be changed”. Here the “adjuster of the rotatedcone” is the adjuster of “the CVT 4 for which the axial position of acone is to be changed”.

And if the “adjuster of the rotated cone” is not the adjuster that isused to reduce the tension in the transmission belt of “the CVT 4 forwhich the axial position of a cone is to be changed”; then here“immediately after the axial position of a cone (referred to as themoved cone) has been changed”, the “adjuster of the rotated cone” shouldbe unlocked so that it can “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline” after the axialposition of the moved cone is changed“; unless motorized adjusters areused in which case the “adjuster of the rotated cone” can be unlockedbefore the axial position of a cone is changed (see below). Also here ifthe adjuster used to reduce the tension in the transmission belt of “theCVT 4 for which the axial position of a cone is to be changed” is notlocked yet, it should be locked first before the “adjuster of therotated cone” is unlocked, unless motorized adjusters are used (seebelow); since here this is one requirement to ensure that at least oneCVT 4 is always used for torque transmission. And here the otherrequirement to ensure that at least one CVT 4 is always used for torquetransmission is that the slack in the tense side tensioningpulley/support pulley of the CVT 4 for which the axial position of acone ‘is to be’/‘was’ changed” is exhausted before the “adjuster of therotated cone” is unlocked (unless motorized adjusters are used). Inorder to ensure that this requirement is met, a “sensor that informs thecontrolling computer when the tense side tensioning pulley/supportpulley of the CVT 4 for which the axial position of a cone is to bechanged hits its maximum contraction stop” can be used to inform thecontrolling computer when to lock the “adjuster of the rotated cone”;but if the “duration for the slack in the tense side tensioningpulley/support pulley of the CVT 4 for which the axial position of acone ‘is to be’/‘was’ changed to exhaust” is insignificant, it might bemore practical to ignore this requirement even if it is desired to haveat least one CVT 4 always used for torque transmission. Anotherpotential benefit of using a “sensor that informs the controllingcomputer when the tense side tensioning pulley/support pulley of the CVT4 for which the axial position of a cone is to be changed hits itsmaximum contraction stop” for unlocking the “adjuster of the rotatedcone” is that through its usage sudden increase in tension in thetransmission belts can be minimized. Here simple experimentation can beused to see whether using a “sensor that informs the controllingcomputer when the tense side tensioning pulley/support pulley of the CVT4 for which the axial position of a cone is to be changed hits itsmaximum contraction stop” in order to unlock the “adjuster of therotated cone” (which is recommended from a performance perspective)provides substantial benefits over simply unlocking the “adjuster of therotated cone” immediately after the axial position of a cone has beenchanged.

Although it is recommended that the “adjuster that was used to reducethe tension in the transmission belt of the CVT 4 for which the axialposition of a cone is to be changed” is locked during axial positionchanging of a cone (so as to avoid shock loads due to locking underload), if this is not practical (such as because the friction in theadjusters is too large to be sufficiently rotated by the tension of thetensioning pulleys/support pulleys, the required rotation for lockingthe index wheel is too large, etc.), then the “adjuster that was used toreduce the tension in the transmission belt of the CVT 4 for which theaxial position of a cone is to be changed” can only be locked after theslack in the tense side tensioning pulley/support pulley of the CVT 4for which the axial position of a cone ‘is to be’/‘was’ changed” isexhausted. In this situation, if the “adjuster of the rotated cone” isunlocked “immediately after the axial position of a cone has beenchanged”, then there might instances where the adjusters of both CVT 4'sare unlocked; this is undesirable since here the cones of the unlockedadjusters can rotate at high speeds relative to their shaft/spline,which can cause shock loads during relocking. In order to avoid this, itis recommended that in this situation a “sensor that informs thecontrolling computer when the tense side tensioning pulley/supportpulley of the CVT 4 for which the axial position of a cone is to bechanged hits its maximum contraction stop” or better yet a “sensor thatinforms the controlling computer when the adjuster that was used toreduce the tension in the transmission belt of the CVT 4 for which theaxial position of a cone is to be changed is locked” is used to informthe controlling computer when to unlock the “adjuster of the rotatedcone”. Proximity sensors, contact sensors, etc. can be used for the“sensors that inform the controlling computer when the tense sidetensioning pulley/support pulley of their CVT 4 hits its maximumcontraction stop” and the “sensors that informs the controlling computerwhen their adjuster is locked and unlocked”.

If it is desired to unlock the “adjuster of the rotated cone” after the“adjuster that was used to reduce the tension in the transmission beltof the CVT 4 for which the axial position of a cone is to be changed” islocked and the slack in its tense side tensioning pulley/support pulleyhas been exhausted (which is recommended from a performanceperspective), then it takes time for the “adjuster of the rotated cone”to unlock. But once the “adjuster used to reduce the tension in thetransmission belt of the CVT 4 for which the axial position of a cone isto be changed” is locked and the slack that can be provided and/orremoved by the tensioning pulleys/support pulleys of its CVT 4 have beenexhausted, then the “CVT 4 for which the axial position of a cone ‘is tobe’/‘was’ changed” will become the CVT 4 used for torque transmission,and the transmission belt tension in the CVT 4 of the rotated conebecomes reduced. Once the transmission belt tension in the CVT 4 of therotated cone is reduced, “its tense side tensioning pulleys/supportpulleys can remove slack and its slack side tensioning pulleys/supportpulleys can provide slack” so as to “compensate for the brief durationwhere there are two cones with different transmission diameters mountedon a same shaft/spline without having an adjuster allowing forcompensating rotation”, this allows some time for the “adjuster of therotated cone” to unlock.

If a motorized adjuster, which is an adjuster that uses an adjustermotor, is used, then in order to unlock the adjuster of the rotatedcone, the adjuster motor should rotate the rotated cone in the direction“the rotated cone will need to rotate in order to “compensate for havingcones with different transmission diameters mounted on a sameshaft/spline” after the axial position of the moved cone is changed”;here the adjuster motor can simply stall or slip when its rotation is“not” or “not yet” needed.

Since a motorized adjuster only allows rotation in the direction itsadjuster motor rotates (so that it does not allow rotation in thedirection that reduces the tension in its transmission belt insituations where “the adjuster of the rotated cone is not the adjusterthat is used to reduce the tension in the transmission belt of the CVT 4for which the axial position of a cone is to be changed”), and cansimply stall, slip, or stop when its rotation is “not” or “not yet”needed. It is recommended that in situations where “the adjuster of therotated cone is not the adjuster that is used to reduce the tension inthe transmission belt of the CVT 4 for which the axial position of acone is to be changed”, a motorized adjuster is unlocked before theaxial position of a cone is changed.

If an adjuster that uses a brake or an indexing mechanism is used, thenin order to unlock the adjuster of the rotated cone, the adjuster shouldbe released/unlocked.

Here the rotated cone should be a cone which needs to be rotated in thedirection that increases the tension in the tense side of itstransmission belt in order to “compensate for having cones withdifferent transmission diameters mounted on a same shaft/spline” afterthe axial position of the moved cone is changed; the selection ofwhether the rotated cone is a cone of the “CVT 4 of the moved cone”, ora cone of the “CVT 4 which is not the CVT 4 of the moved cone” shoulddepend only on this.

Regarding the rotated cone, the CVT 4 for which a cone (the rotatedcone) has to be “unlocked for rotation” in the direction that increasesthe tension in the tense side of its transmission belt in order to“compensate for having cones with different transmission diametersmounted on a same shaft/spline” is a CVT 4 for which its cone on theinput shaft/spline has the smaller transmission diameter relative to theother cone on the input shaft/spline after the axial position changingof a cone of “step c) First axial position changing of a cone” has beencompleted, or a CVT 4 for which its cone on the output shaft/spline hasthe larger transmission diameter relative to the other cone on outputshaft/spline after the axial position changing of a cone of “step c)First axial position changing of a cone” has been completed.

For a rotated cone on the input shaft/spline, the cone's direction ofrotation that increases the tension in the tense side of itstransmission belt is in the direction of rotation of the inputshaft/spline. And for a rotated cone on the output shaft/spline, thecone's direction of rotation that increases the tension in the tenseside of its transmission belt is in the direction opposite from therotation of the output shaft/spline.

After the rotated cone is set-up to be “unlocked” or “left unlocked”,axial position changing of a cone of this step (“step c) First axialposition changing of a cone”) is performed. Axial position changing of acone of this step is performed on a cone (referred to as the moved cone)of “the CVT 4 for which the transmission belt tension was reduced (dueto a releasing torque)”; note: transmission belt tension was reduced instep b).

Here if the “CVT 4 of the moved cone” is also the “CVT 4 of the rotatedcone”, then the transmission diameter of the cone on the inputshaft/spline can be decreased or the transmission diameter of the coneon the output shaft/spline can be increased.

And if the “CVT 4 of the moved cone” is not the “CVT 4 of the rotatedcone”, then the transmission diameter of the cone on the inputshaft/spline can be increased or the transmission diameter of the coneon the output shaft/spline can be decreased.

The CVT 4 for which a cone has to be “unlocked for rotation” in thedirection that increases the tension in the tense side of itstransmission belt in order to “compensate for having cones withdifferent transmission diameters mounted on a same shaft/spline” (whichis the CVT 4 of the rotated cone) is the “CVT 4 for which thetransmission belt tension is reduced (due to required tensioningcompensating rotation)” after the axial position changing of a cone ofthis step (“step c) First axial position changing of a cone”) has beencompleted; since for this CVT 4, a cone has to be “allowed torotate”/“rotated” in the direction that increases the tension in thetense side of its transmission belt in order prevent an excessiveincrease in tension in the transmission belt of the other CVT 4, andsince the torque capacity of an adjuster motor (if used) should be muchsmaller than the pulling torque of its CVT 6 under all operatingconditions so that an adjuster motor will stall/slip before it canincrease the tension in its transmission belt to above the pullingtorque of its CVT 6.

d) Second Axial Position Changing of a Cone Option 1 of 2

After “step c) First axial position changing of a cone”, if desired theaxial position of a cone of the “CVT 4 for which the transmission belttension is reduced (due to required tensioning compensating rotation)”can be changed; this axial position changing of a cone is referred to as“step d) Second axial position changing of a cone Option 1 of 2”.Alternately, after “step c) First axial position changing of a cone, ifdesired “step e) Second axial position changing of a cone Option 2 of 2”(which is described below) can be performed instead of “step d) Secondaxial position changing of a cone Option 1 of 2”.

The “CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)” is the CVT 4 of the rotatedcone (see step c). The rotated cone is the cone that is unlocked so thatit can rotate in the direction that increases the tension in the tenseside of its transmission belt in order to “compensate for having coneswith different transmission diameters mounted on a same shaft/spline”relative to its shaft/spline.

If the “CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)” is the CVT 4 for which theaxial position of a cone was changed in “step c) First axial positionchanging of a cone”, then the transmission belt tension in this CVT 4 isalready reduced after “step c) First axial position changing of a cone”.

If the “CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)” is not the CVT 4 for whichthe axial position of a cone was changed in “step c) First axialposition changing of a cone”, then the transmission belt tension in the“CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)” is reduced after “step c)First axial position changing of a cone” has been completed, and afterthe slack in the tense side tensioning pulley/support pulley of the CVT4 for which the axial position of a cone was changed has been exhausted.Here in order to ensure that the tension in the transmission belt of the“CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)” has been reduced and thatthe tensioning pulleys/support pulleys of the “CVT 4 for which thetransmission belt tension is reduced (due to required tensioningcompensating rotation)” are in their required positions, a pause after“step c) First axial position changing of a cone” has been completed canbe used before starting the axial position changing of a cone of thisstep (“step d) Second axial position changing of a cone Option 1 of 2”).

Here once the tension in the transmission belt of the “CVT 4 for whichthe transmission belt tension is reduced (due to required tensioningcompensating rotation)” has been reduced; when the adjuster, used toprovide/allow compensating rotation (which is achieved by rotating or“allowing rotation of” a cone of said CVT 4 in the direction thatincreases the tension in the tense side of its transmission belt), isunlocked but the “speed its adjuster motor (when used) rotates itsadjuster output shaft” is less than the “speed applied on its adjusteroutput shaft”, then an increase in tension in the slack side of thetransmission belt of the “CVT 4 for which the transmission belt tensionis reduced (due to required tensioning compensating rotation)” canoccur; since here the unlocked cone (the cone of the unlocked adjuster)is rotated relative to its shaft/spline due to the pulling tension inthe slack side of its transmission belt. As such here the slack side ofthe transmission belt (which is the slack side of the transmission beltduring regular torque transmission) becomes the tense side of thetransmission belt, and the tense side of the transmission belt (which isthe tense side of the transmission belt during regular torquetransmission) becomes the slack side of the transmission belt. Here thetensioning forces and the movement ranges of the tensioningpulleys/support pulleys should be selected so that once the tense sidetensioning pulley/support pulley and the slack side tensioningpulley/support pulley have reached their equilibrium positions, thetense side tensioning pulley/support pulley and the slack sidetensioning pulley/support pulley each have a sufficient “contracting andextending movement range” to provide and remove slack as needed to allowfor axial position changing of their cone during axial position changingof their cone.

Alternately, here once the tension in the transmission belt of the “CVT4 for which the transmission belt tension is reduced (due to requiredtensioning compensating rotation)” has been reduced; and for theadjuster used to provide compensating rotation, the “speed its adjustermotor rotates its adjuster output shaft” is more or equal than the“speed applied on its adjuster output shaft”, then the torque of theadjuster motor and the tensioning forces and movement ranges of thetense side tensioning pulley/support pulley and the slack sidetensioning pulley/support pulley should also be selected so that oncethe tense side tensioning pulley/support pulley and the slack sidetensioning pulley/support pulley have reached their equilibriumpositions, the tense side tensioning pulley/support pulley and the slackside tensioning pulley/support pulley each have a sufficient“contracting and extending movement range” to provide and remove slackas needed to allow for axial position changing of their cone.

Here if it is difficult to balance the tensioning forces of the tenseside tensioning pulley/support pulley and the slack side tensioningpulley/support pulley of the “CVT 4 for which the transmission belttension is reduced (due to required tensioning compensating rotation)”so that they each have a sufficient “contracting and extending movementrange”, then a configuration where the slack side tensioningpulley/support pulley hits its maximum contraction stop can be used forsaid CVT, before axial position changing of a cone of said CVT isstarted.

A configuration where the slack side tensioning pulley/support pulleyhits its maximum contraction stop can occur when the adjuster that isused to provide/allow compensating rotation is unlocked but the “speedits adjuster motor (when used) rotates its adjuster output shaft” isless than the “speed applied on its adjuster output shaft”; since herethe unlocked cone is rotated relative to its shaft/spline due to theincreased pulling tension in the slack side of its transmission belt,which when large enough can cause its slack side tensioningpulley/support pulley to hit its maximum contraction stop.

If the slack side tensioning pulley/support pulley hits its maximumcontraction stop, then the tense side tensioning pulley/support pulleycan only provide slack, and the slack side tensioning pulley/supportpulley can only remove slack. But, this can also work here, since herethe adjuster of the CVT 4 for which the axial position of a cone ischanged, is “unlocked for rotation” in the direction that removes slackfrom the side of the tense side tensioning pulley/support pulley andprovides slack to the side of the slack side tensioning pulley/supportpulley.

But, the tension in the slack side of the transmission belt for aconfiguration where the slack side tensioning pulley/support pulley hitsits maximum contraction stop will be larger than that of theconfiguration where the tense side tensioning pulley/support pulley andthe slack side tensioning pulley/support pulley each have a sufficient“contracting and extending movement range”. An increase in tension in atransmission belt (slack side and/or tense side) will increase the forcerequired to axially move a cone that is engaged with said transmissionbelt.

Additionally, here if the unlocked cone is rotated relative to itsshaft/spline due to the pulling tension in the slack side of itstransmission belt, then the worm gear of its adjuster (and as such alsothe unlocked cone) accelerates from standstill until it has reached itssteady state speed. Since the friction in the worm gear-gear drivedecreases as the speed of the worm gear increases, the pulling tensionin the slack side of its transmission belt decreases as the speed of theworm gear increases. As such, here using a “delay to let the unlockedcone speed-up” before changing the axial position of a cone of the CVT 4of the unlocked cone, can reduce the force required to axially move acone of the CVT 4 of the unlocked cone.

Once the tension in the transmission belt of the “CVT 4 for which thetransmission belt tension is reduced (due to required tensioningcompensating rotation)” has been reduced and its tensioningpulleys/support pulleys are in position (which can be ensured through atime delay that can be obtained through trial-and-errorexperimentation), the axial position of a cone of the “CVT 4 for whichthe transmission belt tension is reduced (due to required tensioningcompensating rotation)”, can be changed.

Here if the cone which axial position was changed under “step c) Firstaxial position changing of a cone” was on the input shaft/spline; thenfor “step d) Second axial position changing of a cone Option 1 of 2”,the transmission diameter of the “cone with the smaller transmissiondiameter” on the input shaft/spline needs to be increased so that itstransmission diameter is equal to the transmission diameter of the othercone on the input shaft/spline”. Note: here the “cone with smallertransmission diameter” on the input shaft/spline is a cone of the “CVT 4for which the transmission belt tension is reduced (due to requiredtensioning compensating rotation)”.

And if the cone which axial position was changed under “step c) Firstaxial position changing of a cone” was on the output shaft/spline; thenfor “step d) Second axial position changing of a cone Option 1 of 2”,the transmission diameter of the “cone with larger transmissiondiameter” on the output shaft/spline needs to be decreased so that itstransmission diameter is equal to the transmission diameter of the othercone on the output shaft/spline”. Note: here the “cone with largertransmission diameter” on the output shaft/spline is a cone of the “CVT4 for which the transmission belt tension is reduced (due to requiredtensioning compensating rotation)”.

After the axial position changing of a cone of “step d) Second axialposition changing of a cone Option 1 of 2” has been completed, theadjuster that is used to “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline” should be (butnot necessarily) stopped/braked/locked when possible”, since after theaxial position changing of a cone of “step d) Second axial positionchanging of a cone Option 1 of 2” has been completed, the CVT 6 will beat “step a) Initial Setup/Regular Operation Setup”, where thetransmission diameters of all cones mounted on a same shaft/spline areequal.

e) Second Axial Position Changing of a Cone Option 2 of 2

Alternately, after “step c) First axial position changing of a cone”,instead changing the axial position of a cone of the “CVT 4 for whichthe transmission belt tension is reduced (due to required tensioningcompensating rotation)” under “step d) Second axial position changing ofa cone Option 1 of 2”, if desired the axial position of a cone of the“CVT 4 for which the transmission belt tension is not reduced” can bechanged. This axial position changing of a cone is referred to as “stepe) Second axial position changing of a cone Option 2 of 2”.

Here first the transmission belt tension of the “CVT 4 for which thetransmission belt tension is not reduced” needs to be reduced. This isaccomplished by unlocking (unlocking for rotation) a cone of the “CVT 4for which the transmission belt tension is not reduced” so that it canrotate in the direction that reduces the tension in its transmissionbelt. Here if an adjuster that uses an adjuster motor is used, then inorder to unlock the adjuster, the adjuster needs to rotate its conerelative to its shaft/spline in the direction that reduces the tensionin its transmission belt; and if an adjuster that uses a brake is used,then in order to unlock the adjuster, its brake needs to be released;and if an adjuster that uses an indexing mechanism is used, then inorder to unlock the adjuster, its indexing mechanism needs to beunlocked.

In this situation, the “direction of rotation that reduces the tensionin its transmission belt” a cone of the “CVT 4 for which thetransmission belt tension is not reduced” is also the direction to“compensate for having cones with different transmission diametersmounted on a same shaft/spline”; this is because the direction ofrotation of the “CVT 4 for which the transmission belt tension isreduced (due to required tensioning compensating rotation)” is in thedirection that increases its transmission belt tension, and thedirection of rotation to “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline” of one CVT 4should be opposite from that of the other CVT 4. As such here, a cone ofthe “CVT 4 for which the transmission belt tension is not reduced” needsto be “unlocked for rotation” in the direction that reduces the tensionin its transmission belt (which is also the direction of rotation to“compensate for having cones with different transmission diametersmounted on a same shaft/spline”) as long as there are cones withdifferent transmission diameters mounted on the same shaft/spline.

And since here the rotation to reduce the transmission belt tension ofthe “CVT 4 for which the transmission belt tension is not reduced” alsocompensates for having cones with different transmission diametersmounted on the same shaft/spline, here the rotation of a cone to“compensate for having cones with different transmission diametersmounted on a same shaft/spline” of the “CVT 4 for which the transmissionbelt tension is reduced (due to required tensioning compensatingrotation)” will slow-down so that it can be eventuallystopped/braked/locked. Here, when available, some braking or slowingdown forces can also be applied by the adjuster when the rotation of acone of the “CVT 4 for which the transmission belt tension is reduced(due to required tensioning compensating rotation) is slowing down.

After rotation to reduce the transmission belt tension of the “CVT 4 forwhich the transmission belt tension is not reduced” is started, thetransmission belt tension of the “CVT 4 for which the transmission belttension is not reduced” will eventually become reduced, so that the “CVT4 for which the transmission belt tension is reduced (due to requiredtensioning compensating rotation)” will eventually need to be used asthe CVT 4 used for torque transmission.

Here if an adjuster that uses brake or an indexing mechanism is used forthe “CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)”, then the brake or indexingmechanism needs to be braked/locked after the adjuster of the “CVT 4 forwhich the transmission belt tension is not reduced” is unlocked, sinceat least one adjuster needs to “compensate for having cones withdifferent transmission diameters mounted on a same shaft/spline”.

Here if desired, an adjuster that uses a brake or an indexing mechanismcan be braked/locked after the speed of the worm gear to bebraked/locked has slowed down, so as to reduce the shock-loads duringbraking/locking. If this is desired, then a time delay from when theadjuster of the “CVT 4 for which the transmission belt tension is notreduced” is unlocked until braking/locking of the adjuster of the “CVT 4for which the transmission belt tension is reduced (due to requiredtensioning compensating rotation)” occurs can be used. The time delaydoes not have to be accurate, but for better accuracy, the time delaycan be based on the current rpm and transmission ratio of the CVT 6. Forthe time delay, it is recommended that braking/locking occurs before theworm gear reverses direction since by then the adjuster to bebraked/locked is subjected to the torque being transmitted by the CVT 6(instead of only the torque due to friction). Instead of a time delay, asensor that measures the speed of the worm gear to be braked/locked canalso be used to reduce the shock-loads during braking/locking.

Here if an adjuster that uses an adjuster motor is used, it is importantthat the adjuster of the “CVT 4 for which the transmission belt tensionis reduced (due to required tensioning compensating rotation)”, which isinitially rotating in the direction that increases the tension in itstransmission belt, will not “reverse direction and rotate in thedirection that reduces the tension in its transmission belt” after theadjuster of the “CVT 4 for which the transmission belt tension is notreduced” is unlocked. Since if both adjusters rotate in the directionthat reduces the tension in their transmission belts, then relocking theadjusters can require a large torque. If necessary, here the adjuster ofthe “CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)” applies a braking torque toensure that said adjuster will not reverse direction, but insteadslows-down and eventually stops and becomes locked due to the frictionof its worm gear-gear drive; other means for braking the rotating coneof the “CVT 4 for which the transmission belt tension is reduced (due torequired tensioning compensating rotation)” can also be used.

Here once the tension in the transmission belt of the “CVT 4 for whichthe transmission belt tension is not reduced”, which from now on will bereferred to as the “CVT 4 for which the transmission belt tension isreduced (due to releasing compensating rotation)”, has been reduced;when the adjuster used to provide/allow compensating rotation (which isachieved by rotating or “allowing rotation of” a cone of the “CVT 4 forwhich the transmission belt tension is reduced (due to releasingcompensating rotation)” in the direction that decreases the tension inthe tense side of its transmission belt) is unlocked but the “speed itsadjuster motor (when used) rotates its adjuster output shaft/spline” isless than the “speed applied on its adjuster output shaft/spline”, thenan increase in tension in the tense side of the transmission belt of the“CVT 4 for which the transmission belt tension is reduced (due toreleasing compensating rotation)” can occur; since here the unlockedcone is rotated relative to its shaft/spline due to the pulling tensionin the tense side of its transmission belt. Here the tense sidetensioning pulley/support pulley and the slack side tensioningpulley/support pulley each should have a sufficient “contracting andextending movement range” to provide and remove slack as needed to allowfor axial position changing of their cone during axial position changingof their cone.

Alternately, here once the tension in the transmission belt of the “CVT4 for which the transmission belt tension is reduced (due to releasingcompensating rotation)” has been reduced; and for the adjuster used toprovide compensating rotation, the “speed its adjuster motor rotates itsadjuster output shaft” is more or equal than the “speed applied on itsadjuster output shaft”, then the torque of the adjuster motor and thetensioning forces of the tense side tensioning pulley/support pulley andthe slack side tensioning pulley/support pulley should be selected sothat once the tense side tensioning pulley/support pulley and the slackside tensioning pulley/support pulley have reached their equilibriumpositions, the tense side tensioning pulley/support pulley and the slackside tensioning pulley/support pulley each have a sufficient“contracting and extending movement range” to provide and remove slackas needed to allow for axial position changing of their cone.

Here if it is difficult to balance the tensioning forces of the tenseside tensioning pulley/support pulley and the slack side tensioningpulley/support pulley so that they each have a sufficient “contractingand extending movement range”, then a configuration where the tense sidetensioning pulley/support pulley hits its maximum contraction stop canbe used before axial position changing of a cone of the “CVT 4 for whichthe transmission belt tension is reduced (due to releasing compensatingrotation)” is started.

A configuration where the tense side tensioning pulley/support pulleyhits its maximum contraction stop can occur when the adjuster that isused to provide/allow compensating rotation is unlocked but the “speedits adjuster motor (when used) rotates its adjuster output shaft” isless than the “speed applied on its adjuster output shaft”; since herethe unlocked cone is rotated relative to its shaft/spline due to theincreased pulling tension in the tense side of its transmission belt,which when large enough can cause its tense side tensioningpulley/support pulley to hit its maximum contraction stop.

If the tense side tensioning pulley/support pulley hits its maximumcontraction stop, then the tense side tensioning pulley/support pulleycan only remove slack and the slack side tensioning pulley/supportpulley can only provide slack. But, this can also work here, since herethe adjuster of the CVT 4 for which the axial position of a cone ischanged, is “unlocked for rotation” in the direction that provides slackto the side of the tense side tensioning pulley/support pulley andremoves slack from the side of the slack side tensioning pulley/supportpulley.

But, the tension in the tense side of the transmission belt for aconfiguration where the tense side tensioning pulley/support pulley hitsits maximum contraction stop will be larger than that of theconfiguration where the tense side tensioning pulley/support pulley andthe slack side tensioning pulley/support pulley each have a sufficient“contracting and extending movement range”. An increase in tension in atransmission belt (slack side and/or tense side) will increase the forcerequired to axially move a cone that is engaged with said transmissionbelt.

Additionally, here if the unlocked cone is rotated relative to itsshaft/spline due to the pulling tension in the tense side of itstransmission belt, then the worm gear of its adjuster (and as such alsothe unlocked cone) accelerates from standstill until it has reached itssteady state speed. Since the friction in the worm gear-gear drivedecreases as the speed of the worm gear increases, the pulling tensionin the tense side of its transmission belt decreases as the speed of theworm gear increases. As such, here using a “delay to let the unlockedcone speed-up” before changing the axial position of a cone of the CVT 4of the unlocked cone, can reduce the force required to axially move acone of the CVT 4 of the unlocked cone.

Once the tension in the transmission belt of the “CVT 4 for which thetransmission belt tension is reduced (due to releasing compensatingrotation)” has been reduced and its tensioning pulleys/support pulleysare in position (which can be ensured through a time delay that can beobtained through trial-and-error experimentation), the axial position ofa cone of the “CVT 4 for which the transmission belt tension is reduced(due to releasing compensating rotation)”, can be changed.

Here if the cone which axial position was changed under “step c) Firstaxial position changing of a cone” was on the input shaft/spline; thenfor “step e) Second axial position changing of a cone Option 2 of 2”,the transmission diameter of the “cone with larger transmissiondiameter” on the input shaft/spline needs to be decreased so that itstransmission diameter is equal to the transmission diameter of the othercone on the input shaft/spline”. Note: here the “cone with largertransmission diameter” on the input shaft/spline is a cone of the “CVT 4for which the transmission belt tension is reduced (due to releasingcompensating rotation)”.

And if the cone which axial position was changed under “step c) Firstaxial position changing of a cone” was on the output shaft/spline; thenfor “step e) Second axial position changing of a cone Option 2 of 2”,the transmission diameter of the “cone with smaller transmissiondiameter” on the output shaft/spline needs to be increased so that itstransmission diameter is equal to the transmission diameter of the othercone on the output shaft/spline”. Note: here the “cone with smallertransmission diameter” on the output shaft/spline is a cone of the “CVT4 for which the transmission belt tension is reduced (due to releasingcompensating rotation)”.

After the axial position changing of a cone of “step e) Second axialposition changing of a cone Option 2 of 2” has been completed, theadjuster that is used to “compensate for having cones with differenttransmission diameters mounted on a same shaft/spline” should be (butnot necessarily) stopped/braked/locked when possible”, since after theaxial position changing of a cone of “step e) Second axial positionchanging of a cone Option 2 of 2” has been completed, the CVT 6 will beat “step a) Initial Setup/Regular Operation Setup”, where thetransmission diameters of all cones mounted on a same shaft/spline areequal.

Details Regarding “Transmission Ratio Change Rotation” in a CVT 6 (“BeltCurvature Change Rotation”

As described earlier, Point N is the contact point between a cone andits transmission belt that doesn't rotate due to changes in thetransmission diameter of said cone; and Point M of a cone is the pointwere no rotational sliding between said cone and its torque transmittingmember occur due to axial position change of said torque transmittingmember relative to said cone (see FIG. 6 for an example).

As the transmission diameter of a cone is increased, the length of theportion of the transmission belt covering the cone has to be increased;and as the transmission diameter of a cone is decreased, the length ofthe portion of the transmission belt covering the cone has to bedecreased. Increasing the length of the portion of the transmission beltcovering the cone requires that the portion(s) of the transmission beltto the left and/or to the right of Point N are slid towards Point N soas to provide more slack; this cause relative rotational movementbetween the surface of the cone and its transmission belt except atPoint N. And decreasing the length of the portion of the transmissionbelt covering the cone requires that the portion(s) of the transmissionbelt to the left and/or to the right of Point N are slid away from PointN so as to remove slack; this also cause relative rotational movementbetween the surface of the cone and its transmission belt except atPoint N. “Transmission ratio change rotation” due to the relativerotational movement (sliding) between the surface of a cone and itstransmission belt as described in this paragraph is referred to as “beltcurvature change rotation”.

The direction of “belt curvature change rotation” depends on theposition of Point M relative to Point N, and whether the transmissiondiameter of the cone is increased or decreased. When Point M ispositioned at Point N, “belt curvature change rotation” should be zero;and when Point M is positioned to the left of Point N, the direction of“belt curvature change rotation” should be in the opposite directionfrom when Point M is positioned to the right of Point N. The location ofPoint N and the directions of “belt curvature change rotation” can beobtained through experimentations using a Test CVT.

The amount of “belt curvature change rotation” of a cone depends on thedistance of the Point M of said cone from Point N. If we ignore therotations of said cone due to the rotations of its CVT 6 (forillustrative purposes let's assume that the CVT 6 of said cone is notrotating), then the length of the transmission belt segment from Point Nto Point M remains constant as the axial position of said cone ischanged. If this transmission belt segment is longer than more “beltcurvature change rotation” will occur during transmission diameterchange of said cone.

For example, for 0.2 tooth long transmission belt segment, “beltcurvature change rotation” will be due to the change in curvature ofthat 0.2 tooth. And for a 6 tooth long transmission belt segment, “beltcurvature change rotation” will be due to the change in curvature ofthose 6 teeth. Obviously “belt curvature change rotation” for 6 teeth islarger than that of 0.2 tooth.

As a cone is rotating due to rotations of its CVT 6, “belt curvaturechange rotation” for said cone should continuously decrease when itsPoint M rotates towards Point N, and should continuously increase whenits Point M rotates away from Point N.

Details Regarding “Transmission Ratio Chance Rotation” in a CVT 6(“Member Curvature Chance Rotation”)

“Transmission ratio change rotation” of a cone can also be due to thechange in curvature of the torque transmitting member of said cone. Thistype of “Transmission ratio change rotation” is referred to as “membercurvature change rotation”.

“Member curvature change rotation” occurs when there are portions of atorque transmitting member that are not covered by its transmissionbelt. The amount of “member curvature change rotation” depends on thedistance from “Point M of the torque transmitting member, which must benot covered by its transmission belt, to “the point of engagementbetween said torque transmitting member and its transmission belt”. “Thepoint of engagement between said torque transmitting member and itstransmission belt”, will be referred to as Point E.

If we ignore the rotations of said cone due to the rotations of its CVT6 (for illustrative purposes let's assume that the CVT 6 of said cone isnot rotating), then the length of the torque transmitting member segmentfrom Point M to Point E remains constant as the axial position of saidcone is changed. If this torque transmitting member segment is longerthan more “member curvature change rotation” will occur duringtransmission diameter change of said cone.

For example, for 0.2 tooth long torque transmitting member segment,“belt curvature change rotation” will be due to the change in curvatureof that 0.2 tooth. And for a 6 tooth long torque transmitting membersegment, “member curvature change rotation” will be due to the change incurvature of those 6 teeth. Obviously “member curvature change rotation”for 6 teeth is larger than that of 0.2 tooth.

The direction of “member curvature change rotation” depends on theposition of Point M relative to Point E (note: Point M must not coveredby its transmission belt), and whether the transmission diameter of thecone is increased or decreased. When Point M is positioned at Point E,“member curvature change rotation” should be zero; and when Point M ispositioned to the left of Point E, the direction of “belt curvaturechange rotation” (if it is not zero) should be in the opposite directionfrom when Point M is positioned to the right of Point E. The directionsof “member curvature change rotation” can be obtained throughexperimentations using a Test CVT.

Example of “Transmission Ratio Change Rotation” in a CVT 6

As an example, let's say we have a CVT 6 that uses two CVT 4's for whichthe tensioning pulleys are positioned on the slack side of thetransmission belt. And said CVT 6 uses cones that each have the designof a “cone assembly with one torque transmitting member” described inthe “Alternate CVT's” section of U.S. Pat. No. 7,722,490 B2.

And for said CVT 6, the cones on the input shaft/spline have thelongitudinal slides mounted ends of their torque transmitting members atthe leading end (which is the end of the torque transmitting member thatengages first), and the cones on the output shaft/spline have thelongitudinal slides mounted ends of their torque transmitting members atthe trailing end (which is the end of the torque transmitting memberthat engages last).

The longitudinal slide mounted end of a torque transmitting member isPoint M of the torque transmitting member, which is a point of thetorque transmitting member which rotational position relative to itscone does not change as the axial position of the torque transmittingmember relative to its cone is changed.

A CVT 4 of the CVT 6 (a CVT 6 has two functionally identical CVT 4's) ofthis section is shown as a front-view in FIG. 6. The following labelingare used for FIG. 6: Driving Cone 9, Torque Transmitting Member 9-M1,Driven Cone 10, Torque Transmitting Member 10-M1, Input Spline 11,Output Spline 12, Support Pulley 14, Tensioning Pulley 13. For DrivingCone 9 and Driven Cone 10, the rotational position of their Point M,which for each cone is located at the end of the torque transmittingmember that is mounted to the longitudinal slide, are marked with M; andthe rotational position of their Point N, are marked with N.

For this CVT 6 all cones are mounted on an adjuster. And in order tocompensate/allow for “Transmission ratio change rotation” in a CVT 4,the adjuster 8 of the cone on the input spline and the adjuster 8 of thecone on the output spline of said CVT 4 are rotated in the samedirection during the axial position change of a said cone.

First, let us look at the “12 to 9 o'clock interval” of Driving Cone 9,here when Point M is positioned near the 12 o'clock position, then PointM is positioned to the right of Point N. Here if the transmissiondiameter of Driving Cone 9 is increased, the “belt curvature changerotation” is counter-clockwise; and if the transmission diameter ofDriving Cone 9 is decreased, then the “belt curvature change rotation”is clockwise.

If the axial position of Driving Cone 9 is changed such that itscircumference increases or decreased by one tooth (as needed to allowfor proper engagement), then for the configuration shown in FIG. 6, themaximum “belt curvature change rotation” for the portions of thetransmission belts covering the surfaces of Driving Cone 9 to the leftand to the right of Point N is “half a tooth”.

For the “12 to 9 o'clock interval” of Driving Cone 9, the ball parkrotational speed and angular acceleration of the adjusters 8 can beestimated by assuming that the maximum “belt curvature change rotation”for the portion of the transmission belt to the right of Point N of“half a tooth” has to be compensated/allowed as Point M is rotated fromthe 12 o'clock position to the 9 o'clock position. Here the distancethat needs to be traveled is “half a tooth”, and the time the distanceneeds to be traveled is the time it takes to rotate Point M from the 12o'clock position to the 9 o'clock position.

The estimate of the previous paragraph is very conservative, since theaxial position changing of Driving Cone 9 should be started when thenot-Point M end of Torque Transmitting Member 9-M1 disengages with itstransmission belt. As such, the speed of “belt curvature changerotation” due to the axial position change of Driving Cone 9 near the 12o'clock position is very low since it starts at zero and thencontinually accelerates as it approaches the 9 o'clock position. Andsince the amount of “belt curvature change rotation” also depends on thedistance of Point M from Point N; at the maximum distance between PointM from Point N, the amount of “belt curvature change rotation” ismaximum (which here is “half a tooth”); and as Point M rotates towardsPoint N it continually decreases until it reaches zero. We roughlyestimate that this will reduce the required rotational speed and angularacceleration by about a half to a quarter (with more time an accurateequation can be obtained).

Therefore, here instead of using a distance of “half a tooth”, we canuse a distance of “half a tooth” to an “eight of a tooth” in calculatingthe ball park rotational speed and angular acceleration for the “12 to 9o'clock interval” of Driving Cone 9. This estimate is only due to “beltcurvature change rotation”, since for the “12 to 9 o'clock interval” ofDriving Cone 9, “member curvature change rotation” for Driving Cone 9 iszero; this is because the distance from “Point M” to “Point E (whichhere is the point of engagement between said torque transmitting memberand its transmission belt at the Point M end of said torque transmittingmember)” is zero.

Next we look at the “9 to 3 o'clock interval” of Driving Cone 9. WhenPoint M of Driving Cone 9 has rotated to Point N (which is at the 9o'clock position), the direction of rotation of “Transmission ratiochange rotation” (which here is only due to “belt curvature changerotation”) will change. When Point M is at Point N “Transmission ratiochange rotation” is zero. And as Point M rotates away from Point N,“belt curvature change rotation” will continue to increase.

And once Point M has rotated so that it is not engaged with itstransmission belt anymore (which is close to the 4.5 o'clock position),“member curvature change rotation” will become non-zero and continue toincrease; since the distance from “Point M” to “Point E (which here isthe point of engagement between said torque transmitting member and itstransmission belt at the not-Point M end of said torque transmittingmember)” continuous to increase.

For the “9 to 3 o′clock interval” of Driving Cone 9, in order todetermine the ball park rotational speed and angular acceleration of theadjusters 8, we use “half a tooth” (which is due to “belt curvaturechange rotation”) plus “one tooth” (which is due to “member curvaturechange rotation”) for the distance, and the time the distance needs tobe traveled is the time it takes to rotate Point M from the 9 o'clockposition to the 3 o'clock position.

As explained previously the movements of a tensioning pulley, such asTensioning Pulley 13, can also be used to provide and remove slack asneeded in order to allow for “Transmission ratio change rotation” due tomovements in the slack side of the transmission belt. For Driving Cone9, Tensioning Pulley 13 cannot allow for “Transmission ratio changerotation” when Point M is positioned to the right of Point N (since hereit is due to movements in the tense side of the transmission belt), butit can allow for “Transmission ratio change rotation” when Point M ispositioned to the left of Point N, as is the case for the “9 to 3o'clock interval” of Driving Cone 9 (since here it is due to movementsin the slack side of the transmission belt).

Since we use Tensioning Pulley 13 to allow for “Transmission ratiochange rotation” due to movements in the slack side of the transmissionbelt, the distance due to “belt curvature change rotation” for the “9 to3 o'clock interval” of Driving Cone 9 can be eliminated, so that saiddistance becomes “one tooth” (which is due to “member curvature changerotation”). This distance is a conservative estimate, since the distanceof “one tooth” due to “member curvature change rotation” is coveredduring the entire duration that the axial position of Driving Cone 9 ischanged and not only the “9 to 3 o'clock interval” of Driving Cone 9.

Next we look at the “9 to 3 o'clock interval” of Driven Cone 10. Herethe distance that needs to be provided by the adjusters 8 in order tocompensate for “Transmission ratio change rotation” as Point M of DrivenCone 10 is rotated from the 9 o'clock position to the 3 o'clock positioncan be estimated to be “half a tooth” (which is due to “belt curvaturechange rotation”) plus “one tooth” (which is due to “member curvaturechange rotation”).

But since “Transmission ratio change rotation” for the “9 to 3 o'clockinterval” of Driven Cone 10 occurs on the slack side of the transmissionbelt, here we use Tensioning Pulley 13 to allow for “Transmission ratiochange rotation” due to “belt curvature change rotation”, so that saiddistance becomes “one tooth” (which is due to “member curvature changerotation”). This distance is a conservative estimate, since the distanceof “one tooth” due to “member curvature change rotation” is coveredduring the entire duration that the axial position of Driven Cone 10 ischanged and not only the “9 to 3 o'clock interval” of Driven Cone 10.

Next we look at the “3 to 12 o'clock interval” of Driven Cone 10. WhenPoint M of Driven Cone 10 has rotated to Point N (which for Driven Cone10 is at the 3 o'clock position), the direction of rotation of“Transmission ratio change rotation” (which here is only due to “beltcurvature change rotation”) will change. When Point M is at Point N“Transmission ratio change rotation” is zero. And as Point M rotatesaway from Point N, “belt curvature change rotation” will continue toincrease. Here the distance that needs to be provided by the adjusters 8in order to compensate/allow for “Transmission ratio change rotation” asPoint M of Driven Cone 10 is rotated from the 3 o'clock position to the12 o'clock position can be estimated to be “half a tooth” (which is dueto “belt curvature change rotation”) plus “zero” (which is due to“member curvature change rotation”).

But, the CVT 6 of this example is designed so that the actual distanceto compensate for “Transmission ratio change rotation” for the “3 to 12o'clock interval” of Driven Cone 10 is less than “half a tooth”. If weestimate that the axial position of Driven Cone 10 is changed during aninterval from “9 to 12 o'clock”, then the “3 to 12 o'clock interval”represents only ⅓ of the total arc length of the “9 to 12 o'clock”interval. In addition, it is desirable to complete the majority of theaxial position changing movement of a cone early on so that the endportion of the axial position changing procedure can be used to reducethe speed of the cone so as to minimize shock loads. If the axialposition changing movement of Driven Cone 10 is less than half of thetotal movement, then the distance to compensate/allow for “Transmissionratio change rotation” should also be less than “half a tooth”, sincethe maximum amount of “Transmission ratio change rotation” of a cone(ignoring reduction due to the distance of Point N from Point M) isproportional to the amount of the axial movement of a cone. Note, theactual interval for changing the axial position of Driven Cone 10 mightbe different than the estimate given above; changing the axial positionof Driven Cone 10 (and also Driving Cone 9) should be performed duringan interval that starts after the trailing end of its torquetransmitting member disengages, and ends before the leading end of itstorque transmitting member re-engages.

After going through all the operating conditions of the adjusters 8, weconclude that the most demanding requirement for the adjusters 8 occurduring the “3 to 12 o'clock interval” of Driven Cone 10, for which thedistance that needs to be traveled is “half a tooth”. If at the smallesttransmission diameter of a cone the transmission circumference is 20teeth, then the arc length of “half a tooth” is 0.5/20×360 degrees=9degrees=0.157 radians. The “3 to 12 o'clock interval” covers 90 degrees,if the maximum operating rpm speed of a cone is 6000 rpm, then t(time)=90 degrees/(6000×360 degrees/60 seconds)=0.0025 seconds. Therequired rotational angular acceleration is =2×0.157 radians/(0.0025seconds)̂2=50240 radians/secondŝ2. The required rotational speed is=12560×0.005 radians/seconds=1199 rpm.

From the angular acceleration, the torque requirement of the adjusters 8can be calculated. Here we assume that each adjuster 8 comprises of anelectric motor that drives a worm gear that drives a gear. The Torque(T)=I×angular acceleration. For I, we use the estimate for the inertiaof the worm gear which is I=0.5×m×r̂2=0.5×0.3 kg×(0.008 m)̂2=9.7×10̂−6 kgm̂2. Plugging everything in we get T=9.7×10̂−6×12560 Nm=0.49 Nm. Thistorque estimate does not include the torque required to overcomefriction, this torque can be calculated/estimated separately and addedto torque estimate above.

If the “input/output ratio” of the worm gear-gear drive is not 1:1, thenappropriate adjustments need to be made to the calculations of theprevious paragraphs in order to determine the ratings for the motorsthat drive the worm gears of the adjusters 8. It might also be desirableto use some gearings that increase the output speed of said motors, butreduce the output torque of said motors and add additional inertia thatneeds to be accelerated by said motors.

Through trial-and-error and experimentation, this ball park estimate canthen be used to obtain the actual required speed and torque ratings ofthe adjuster(s) 8 that allow the axial positions of Driving Cone 9 andDriven Cone 10 to be changed without interruption due to “Transmissionratio change rotation” for the maximum operating speed of the CVT, bysimply testing the at what minimum speed and minimum torque of theadjuster(s) 8 the axial positions of Driving Cone 9 and Driven Cone 10can changed without interruption due to “Transmission ratio changerotation” at the maximum operating speed of the CVT.

As the speed of a worm gear-gear drive increases, its “locking friction”can drop to less than half its static “locking friction”. And as such,at high speeds the “worm rotating force” of a worm gear-gear drive mightbe larger than the “worm locking force” and can be used to accelerateand rotate the worm gear as required to compensate/allow for“Transmission ratio change rotation”. If this is so, then the speedrequirements of the motors of the adjusters 8 can be limited to thespeed at which the “locking friction” will drop significantly to allowthe “worm rotating force” to accelerate and rotate the worm gear asrequired to compensate/allow for “Transmission ratio change rotation”.It is recommended that the motors of the adjusters 8 are always ON whenthe adjusters 8 are needed to compensate/allow for “Transmission ratiochange rotation”, even when the adjusters 8 are driven by the“Transmission ratio change rotation”; this is to account for suddendecrease in speed and increase in “locking friction” of the wormgear-gear drive. Throughout this application, for an adjuster that has aworm gear-gear drive, the definition of an unlocked adjuster is anadjuster for which the “worm rotating force” of its worm gear-gear driveis larger than the “worm locking force” of its worm gear-gear drive.

If two adjusters 8 on a common shaft/spline are used to compensate/allowfor “Transmission ratio change rotation”, then the adjuster 8 on theshaft/spline that is transmitting torque and that is rotating in theopposite direction of a releasing torque, can become unlocked as tofreewheel (not transmitting any torque). This can occur as the adjuster8 reverses direction while rotating under non-static friction. If theadjuster 8 does not have sufficient torque to prevent freewheeling,freewheeling can be stopped by temporarily disengaging the CVT from itssource of power and then using the motor of the adjuster 8 as needed tolock its adjuster 8. This method can be used to stop freewheeling forall situation.

Just getting a CVT 6 to work can be easily achieved by limiting thedemand (torque & speed) of the CVT 6 and/or by selecting adjusters 8with sufficient amount of torque and speed. The purpose of theadditional description of the previous paragraphs is to provideadditional design options that can be used to design a morecost-effective CVT 6.

Miscellaneous Details for a CVT 6

For the CVT 6 shown in FIG. 6, a cone that has the longitudinal slidemounted end of its torque transmitting member at the trailing end, canbe the mirror image of a cone that has the longitudinal slide mountedend of its torque transmitting members at the leading end; except thatif non-symmetrical teeth are used, then for both cones the teeth fortheir torque transmitting members should be oriented so that they cantransfer maximum torque in the direction they are primarily used fortorque transmission.

The designation “leading end” and “trailing end” for the ends of thetorque transmitting member of the example of a “cone assembly with onetorque transmitting member” described in the “Alternate CVT's” sectionof U.S. Pat. No. 7,722,490 B2 were arbitrarily selected. Obviously thepart of a cone referred to as the “leading end” can be used as theleading end of a torque transmitting member (which is the end of atorque transmitting member that engages first) or the “trailing end” ofa torque transmitting member (which is the end of a torque transmittingmember that engages last), and likewise the “trailing end” part of acone can also be used as the “leading end” or “trailing end” of a torquetransmitting member.

The required relative rotation between the cones on a commonshaft/spline to compensate for “Transmission ratio change rotation” canalso be provided by adjuster(s) 8 of the CVT 4 other then the CVT 4 forwhich for a cone rotation to allow for “Transmission ratio changerotation” is required. The same direction of relative rotation betweenthe cones, as described earlier, need to be provided by said adjuster(s)8. However, here the torque required by the adjuster(s) might be larger.

The cones of a CVT 6 should be designed so that they can handle themaximum releasing torque and the maximum torque due to the “rotations tocompensate for having cones with different transmission diametersmounted on a same shaft/spline”. The pulling direction of a releasingtorque is in the direction that increases the tension in the slack sideof the transmission belt. And the pulling direction due to the“rotations to compensate for having cones with different transmissiondiameters mounted on a same shaft/spline” is in direction that increasesthe tension in the slack side of the transmission belt when a cone onthe input shaft/spline is pulled in the direction its CVT is rotating bythe cone to which it is coupled (which should happen occasionally forthe preferred CVT 6), and when a cone on the output shaft/spline ispulled in the opposite direction its CVT is rotating by the cone towhich it is coupled (which should also happen occasionally for thepreferred CVT 6). The pulling direction in the direction that increasesthe tension in the slack side of the transmission belt is opposite fromthe main pulling direction of the cones, which is in the direction thatincreases the tension in the tense side of the transmission belt. Assuch the cones of a CVT 6 should be designed such that can transittorque in both directions as required; although the torque capacity inone direction can be larger than the other.

For a CVT 6, the force needed to change the transmission ratio can bereduced by reducing the tension in the transmission belt of the CVT 4for which the transmission ratio is changed. The transmission ratio ofsaid CVT 4 can be changed by changing the axial position(s) of thedriven cone, driving cone, or both driven cone and driving cone of saidCVT 4.

For a CVT 6, it's recommended that during non-transmission ratiochanging operation, the transmission diameters of the cones mounted on acommon shaft/spline are identical; if this is not the case then theadjuster(s) need to provide rotational adjustments as necessary tocompensate for having cones with unequal transmission diameters on acommon shaft/spline, which reduces efficiency. The required directionfor this rotational adjustment can be obtained through experimentation;here if desired the Test CVT described earlier can be used. Also, it isrecommended that here the adjuster(s) provide more adjustments thanrequired or are unlocked so that they can always provide the amount ofadjustment needed and only stall or slip when they provide too muchadjustment.

Also for the cones of the CVT 6 that do not have an adjuster, it is notnecessary to mount them on their spline through the use of a slider.Other means of mounting as described in U.S. patent application Ser. No.11/978,456, U.S. patent application Ser. No. 13/629,613, and U.S. Pat.No. 7,722,490 B2 can also be used.

A CVT that is identical to the one shown in FIG. 5, except for using anadjuster for each cone, is shown in FIG. 8. The same labeling used forFIG. 5 is used for FIG. 8. For this CVT, the rotational position of onecone at a time of a CVT 4 (driving cone or driven cone) can be rotatedby the adjusters into a moveable position during parking. In order to dothis, for said CVT 4 the adjusters of the driving cone and driven coneare rotated in a common direction until the cone that was to be rotatedinto a moveable position is in that position. Here the requiredrotational speed of the adjusters might be different, this problem canbe solved by simply letting the adjuster that rotates too fast stall,slip, and/or slowdown. Once a cone is in a moveable position, its axialposition can be changed.

When parked, during the axial position changing procedure of a cone, theadjusters are not required to provide a releasing torque unless there istension in the transmission belt that needs to be relieved. Here tensionin transmission belt is unlikely, especially after the adjusters areused to change the rotational positions of the cones. However, ifdesired the tension in transmission belt can be relieved by rotating acone of that transmission belt in both directions, since one directionwill be the direction to relieve tension and the torque of the adjustersare limited so that they should not be able significantly increase thetension in a transmission belt in whichever direction they are rotating.The duration of each rotation of the rotations in both directions can beset by a “set time duration” (the earlier description regarding a “settime duration” is also applicable here). When parked, there is no needto “compensate for having cones with different transmission diametersmounted on a same shaft/spline”.

When the adjusters 8 (adjusters) are only used to release tension,compensate/allow for “Transmission ratio change rotation”, and“compensate for having cones with different transmission diametersmounted on a same shaft/spline”, the only control required for theadjusters is ON/OFF and the direction of rotation; since here theadjusters can always be rotated up to their maximum capacity when ON.Under regular driving conditions having to change the transmission ratioof a CVT during parking, for which rotational position control of a coneis required, is not needed. But, if the cost of an adjuster that allowsfor rotational position control is not cost prohibitive, being able tochange the transmission ratio of a CVT during parking allows the CVT tooperate optimally even under extreme driving conditions.

A CVT 6 uses two CVT 4's in order to reduce the tension in thetransmission belt of one of the CVT 4's. The concept of using two CVT'sand mounting at least one means for conveying torque (such as a cone,transmission pulley, variator, etc.) of each CVT using an “adjuster thatallows a said means for conveying torque to rotate relative to theshaft/spline on which it is mounted” can also be applied to other CVT's.For example, the same concept can be applied to a CVT that uses two CVT1's or two CVT 3's of U.S. Pat. No. 7,722,490 instead of two CVT 4's.For the CVT 1's and CVT 3's it is recommended that the cones of theseCVT's are cones with two opposite slideable teeth.

For the preferred CVT 6 shown in FIG. 5, the adjusters 8 are mounted ona common shaft/spline. A preferred CVT 6 uses two substantiallyidentical CVT 4's, for which each CVT 4 uses an adjuster 8 to mount acone. An adjuster 8, which comprises of an adjuster body 8-M1 andadjuster output shaft 8-M2, can be used to adjust the rotationalposition of the cone mounted to it relative to the shaft/spline on whichit is mounted. It doesn't matter of which shaft/spline of their CVT 4the adjusters are mounted. As such, the adjusters 8 of a CVT 6 can alsobe mounted on different shafts/splines. A preferred CVT 6 where theadjusters 8 are mounted on different splines is shown in FIG. 9.

CVT with TransmissionsCVT with Pre-Transmission

Under most regular driving conditions, the engine of vehicle onlyrevs-up to about half of its maximum rpm. However, under certain drivingcondition (i.e. driving uphill, towing), the maximum power of the engineis required so that the engine needs to rev-up to its maximum rpm. Inorder to limit the input speed into a CVT, a transmission, which isreferred to as a pre-transmission, can be placed between theengine/motor and the CVT. The pre-transmission should have one gearratio for regular driving, and at least one gear ratio for high torquedriving. The gear ratio for high torque driving should be selected so asto reduce the input speed and increase the torque of the rotation thatenters the CVT. If desired, the pre-transmission can also have neutraland/or reverse gearing. A configuration of a drive system using aPre-transmission is shown in FIG. 10.

The purpose of the Pre-transmission is to limit the maximum rotationalspeed of a cone. Another method to accomplish this is by limiting themaximum rotational speed cone is allowed to rotate. Here the engine canstill be allowed to rotate at its maximum rpm, but the transmissionratio of the CVT should be limited so that the maximum rotational speedof a cone is limited to a pre-set maximum rotational speed for a cone.

CVT with Post-Transmission

Under most regular driving conditions, a vehicle only speeds-up to 80mph. In order to accommodate for faster speed, a transmission, which isreferred to as a post-transmission, can be placed after the output ofthe CVT. The post-transmission should have one gear ratio for regulardriving, and at least one gear ratio for high torque driving. Ifdesired, the post-transmission can also have neutral and/or reversegearing. A configuration of a drive system using a Post-transmission isshown in FIG. 11.

CVT with Pre-Transmission and Post-Transmission

If desired drive system can also have a pre-transmission andpost-transmission, both which are described earlier. A configuration ofa drive system using a Pre-transmission and Post-transmission is shownin FIG. 12.

Example of a CVT with a Pre-Transmission and a Post-Transmission

An example drive system that has a pre-transmission, a CVT, and apost-transmission is described below and shown in FIG. 13; it isreferred to as a Drive System 1. Obviously many other configurations andcontrol schemes besides the one described in this example can be usedfor a drive system that has a CVT, and a pre-transmission and/orpost-transmission.

The pre-transmission of Drive System 1 has the following gearing:Neutral, Reverse, Normal (for regular demand driving conditions), andHi-demand (for high demand driving conditions). The Hi-demand gearingcan consist of one or several gear ratios.

The post-transmission of Drive System 1 has the following gearing:Normal (for regular speed driving conditions), and Hi-speed (for highspeed driving conditions). The Hi-speed gearing can consist of one orseveral gear ratios.

Let's say we have an engine with redline of 6000 rpm. Under normaldriving conditions, running said engine up to 3000 rpm is sufficient.Hence, here we use the Normal gearing of the pre-transmission for enginespeeds up to 3000 rpm. And for engine speeds greater than 3000 rpm weuse the Hi-demand gearing(s).

Switching between Normal gearing and Hi-demand gearing can be performedautomatically or manually. Automatic switching can be performed by acontrol mechanism that monitors the rpm speed of the engine. And manualswitching can be performed by the user whenever he senses a Hi-demandcondition, such as driving uphill or towing for example.

The output transmission ratio of Drive System 1 is the transmissionratio involving the pre-transmission, CVT, and post-transmission. Atransmission control system, which has the required output transmissionratio for given output speed and demand driving condition programmedinto it, is used to control the output transmission ratio of DriveSystem 1 based on: a) the output speed of Drive System 1; b) whether itspre-transmission is in Normal gearing or Hi-demand gearing (the demanddriving condition).

The transmission control system is programmed so that the outputtransmission ratio for Hi-demand gearing is lower than that for Normalgearing (for a lower transmission ratio, the torque/speed ratio ishigher than that of a higher transmission ratio). And programmed so thatfor each demand driving condition (Normal and Hi-demand), the lower theoutput speed, the lower the output transmission ratio.

Immediately after switching from Normal gearing to Hi-demand gearing andimmediately after switching from Hi-demand gearing to Normal gearing,the output transmission ratio of Drive System 1 is adjusted by thetransmission control system based on the output speed of Drive System 1and the demand driving condition (Normal or Hi-demand). This isaccomplished by making adjustments in the CVT and/or Post transmissionto reach the required programmed output transmission ratio using the“transmission configuration of Drive System 1” for the demand drivingcondition.

Regarding the “transmission configuration of Drive System 1”: a) forHi-demand gearing, as the output transmission ratio is increased fromthe lowest transmission ratio to the highest transmission ratio, thepost-transmission is used before the CVT is used, since for Hi-demanddriving conditions the Hi-speed feature of the post-transmission willnot be used, and the transmission ratio of the post-transmission can bechanged faster than that of the CVT; b) for Normal gearing, as thetransmission ratio is increased from the lowest transmission ratio tothe highest transmission ratio, the CVT is used first until its highesttransmission ratio is reached before the post-transmission is used.

Under most driving conditions Drive System 1 will provide CVTperformance, while allowing its CVT to operate at a lower maximum rpm.Like the Hi-demand gearing of the pre-transmission, the Hi-speed gearingof the post-transmission is also only used occasionally. As a numericalexample, for a car with 20 inch tires, an engine speed of 3000 rpm, anda 1:1 transmission ratio, the car's speed is =3000 rpm*3.14*20=188400in/min=287 km/h. Under the same set-up, for an engine speed of 2000 rpm,the car's speed is 191 km/h. If the transmission ratio range of the CVTis from 4:1 (lowest trans. ratio) to 1:1 (highest trans. ratio), then itwill be able to provide a car with a speed up to 191 km/h while runningthe engine up to 2000 rpm, which is in range of normal operatingconditions of a car.

Maximum Axial Position Changing RPM Methods

For the “Maximum Axial Position Changing RPM Method”, the CVT isoperated under three operating modes which are: “Normal DrivingConditions” mode, “High Torque Driving Conditions” mode, and “High SpeedDriving Conditions” mode. Here a controlling computer selects whichoperating mode to be used for the CVT, either automatically or due tothe manual selection of the driver.

Also, the “High Torque Driving Conditions” mode is separated into twooperating modes, which are the “Low Transmission Ratio-High TorqueDriving Conditions” mode and the “High Transmission Ratio-High TorqueDriving Conditions” mode.

For the “Maximum Axial Position Changing RPM Method”, “the maximum speedof the input shaft at which the axial position of a cone mounted on itis changed” and “the maximum speed of the output shaft at which theaxial position of a cone mounted on it is changed” are each limited totheir “maximum axial position changing rpm value”.

The “maximum axial position changing rpm value” of the input shaft andthe “maximum axial position changing rpm value” of the output shaft canbe identical or different. When different, the input shaft and theoutput shaft each have their own “maximum axial position changing rpmvalue”.

The purpose of the “maximum axial position changing rpm value(s)” is tolimit the rpm (speed) of the shafts at which axial position changing of“the cones mounted on them” is performed. As such, axial positionchanging of a cone is only performed when the speed of the shaft of saidcone has not exceeded its “maximum axial position changing rpm value”.

In order to allow for reliable axial position changing of a cone of aCVT, the “maximum axial position changing rpm value” of the shaft ofsaid cone should be selected such that when said shaft is rotating atsaid “maximum axial position changing rpm value”, then axial positionchanging of said cone can be performed for all operating conditions ofits CVT, even when said shaft is suddenly fully accelerated.

And for a CVT 6, the “maximum axial position changing rpm value” of ashaft should also be selected such that a complete sequence of steps ofthe “preferred transmission ratio changing procedure for a CVT 6” can beperformed for all operating condition of its CVT, even when said shaftis suddenly fully accelerated.

Experimentation can be used to determine a “maximum axial positionchanging rpm value”. In addition, factors of safety, conservativeestimates, etc. can be used to ensure the reliability of a “maximumaxial position changing rpm value”.

Although the maximum rpm of the input shaft and the maximum rpm of theoutput shaft at which the axial positions of their cones can be changedare limited to their “maximum axial position changing rpm value”, themaximum rpm of the input shaft and the maximum rpm of the output shaftare not limited for the “High Torque Driving Conditions” mode and the“High Speed Driving Conditions” mode. Hence, the maximum power of anengine can be utilized for the “High Torque Driving Conditions” mode and“High Speed Driving Conditions” mode.

The CVT using the “Maximum Axial Position Changing RPM Method” is in the“Normal Driving Conditions” mode when it is not in the “Low TransmissionRatio-High Torque Driving Conditions” mode (see below), and thetransmission ratio of the CVT is from the “lowest (intial) transmissionratio” to a “transmission ratio at which a predetermined cruising speedcan be reached at a predetermined reasonable engine rpm”. For thistransmission ratio range of the “Normal Driving Conditions” mode, “themaximum rpm of the input shaft” and “the maximum rpm of the outputshaft” are limited to their “maximum axial position changing rpm value”regardless of the input (gas pedal depression) of the driver.

And the CVT is also in the “Normal Driving Conditions” mode when the“Low Transmission Ratio-High Torque Driving Conditions” mode iscurrently not manually selected, and the transmission ratio of the CVTis from the “transmission ratio at which a predetermined cruising speedcan be reached at a predetermined reasonable engine rpm” to the “highest(final) transmission ratio”, as long as the “maximum axial positionchanging rpm value” for both the input shaft and the output shaft arenot exceeded. Here if the driver depresses the gas pedal far enough suchthat the “maximum axial position changing rpm value” for either theinput shaft or output shaft is exceeded, the CVT will automaticallyenter the “High Transmission Ratio-High Torque Driving Conditions” mode.

For the “Low Transmission Ratio-High Torque Driving Conditions” mode,the “maximum rpm of the input shaft” and the “maximum rpm of the outputshaft” are not limited to their “maximum axial position changing rpmvalue”. The CVT is in the “Low Transmission Ratio-High Torque DrivingConditions” mode when the transmission ratio of the CVT is from the“lowest (intial) transmission ratio” to a “transmission ratio at which apredetermined cruising speed can be reached at a predeterminedreasonable engine rpm” and the controlling computer of the CVT sensesthat its vehicle is in a “high torque required” situation, such as whenthe controlling computer senses that the depression of the gas pedalresults in a lower than usual speed increase of the input shaft or whenthe gas pedal is suddenly/violently depressed for example.

The CVT can also be in the “Low Transmission Ratio-High Torque DrivingConditions” mode when the “Low Transmission Ratio-High Torque DrivingConditions” mode is manually selected by the driver. Examples ofsituations where manually selecting the “Low Transmission Ratio-HighTorque Driving Conditions” mode can be useful are driving uphill andpulling.

When the CVT is in the “Low Transmission Ratio-High Torque DrivingConditions” mode, transmission ratio changing can still be performed aslong as the speed of each shaft of “the cone(s) for which the axialposition(s) is/are changed” does not exceeded its/their “maximum axialposition changing rpm value”.

The CVT is in the “High Transmission Ratio-High Torque DrivingConditions” mode when the transmission ratio of the CVT is in the hightransmission ratio range, which is the transmission ratio range from the“transmission ratio at which a predetermined cruising speed can bereached at a predetermined reasonable engine rpm” to the “highest(final) transmission ratio”, and the driver depresses the gas pedal deepenough so that the “maximum axial position changing rpm value” for atleast one shaft is exceeded. This allows the driver to use the fullpower of the engine for this transmission ratio range when needed.

For the “transmission ratios below the high transmission ratio range”,the CVT will remain in the “Normal Driving Conditions” mode when the“Low Transmission Ratio-High Torque Driving Conditions” mode is notselected (automatically or through manual selection by the driver) bythe controlling computer regardless of the input (gas pedal depression)of the driver. The reason for this is because for the “transmissionratios below the high transmission ratio range”, less power is neededfor acceleration since the transmission ratios are lower, and becausethis allows a cruising speed to be reached at a reasonable engine rpmwithout having to slow down the vehicle to allow for transmission ratiochanges in the CVT. Using a car with a 3 to 5 gear manual transmissionas an example, a transmission/gear ratio where a cruising speed can bereached at a reasonable engine rpm is a 3rd gear, while a 1st gear isnot.

The CVT is in the “High Speed Driving Conditions” mode when it is at itsfinal (highest) transmission ratio. For the “High Speed DrivingConditions” mode the “maximum rpm of the input shaft” and the “maximumrpm of the output shaft” are not limited, so as not to limit the speed avehicle to the “maximum axial position changing rpm value(s)”. When aCVT is in the “High Speed Driving Conditions” mode, transmission ratiochanging can still be performed as long as the speed of each shaft of“the cone(s) for which the axial position(s) is/are changed” does notexceeded its/their “maximum axial position changing rpm value”.

If desired (but not necessary), in order to provide additionaltransmission ratios for the “High Speed Driving Conditions” mode, a PostTransmission can be placed after the output of the CVT. A PostTransmission can be a regular gear box that has a regular gearing andone or several high speed gearing(s). If desired, the Post Transmissioncan also have neutral and/or reverse gearing. A configuration of a drivesystem using a Post Transmission is shown in FIG. 11.

Alterations to the “Maximum Axial Position Changing RPM Method” of theprevious paragraphs can be made, an example is described as the“Alternate Maximum Axial Position Changing RPM Method” below.

Like the “Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method”, “the maximumspeed of the input shaft at which the axial position of a cone mountedon it is changed” and “the maximum speed of the output shaft at whichthe axial position of a cone mounted on it is changed” are each limitedto their “maximum axial position changing rpm value”.

And like the “Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method”, the purpose ofthe “maximum axial position changing rpm value(s)” is to limit the rpm(speed) of the shafts at which axial position changing of “the conesmounted on them” is performed. As such, axial position changing of acone is only performed when the speed of the shaft of said cone has notexceeded its “maximum axial position changing rpm value”.

And like the “Maximum Axial Position Changing RPM Method”, in order toallow for reliable axial position changing of a cone of a CVT, the“maximum axial position changing rpm value” of the shaft of said coneshould be selected such that when said shaft is rotating at said“maximum axial position changing rpm value”, then axial positionchanging of said cone can be performed for all operating conditions ofits CVT, even when said shaft is suddenly fully accelerated.

And like for the “Maximum Axial Position Changing RPM Method”, for a CVT6, the “maximum axial position changing rpm value” of a shaft shouldalso be selected such that a complete sequence of steps of the“preferred transmission ratio changing procedure for a CVT 6” can beperformed for all operating condition of its CVT, even when said shaftis suddenly fully accelerated.

Like the “Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method”, the CVT is alsooperated under three operating modes which are: “Normal DrivingConditions” mode, “High Torque Driving Conditions” mode, and “High SpeedDriving Conditions” mode. But unlike the “Maximum Axial PositionChanging RPM Method”, for the “Alternate Maximum Axial Position ChangingRPM Method”, the “High Torque Driving Conditions” mode is not separatedinto the “Low Transmission Ratio-High Torque Driving Conditions” modeand the “High Transmission Ratio-High Torque Driving Conditions” mode.

For the “Alternate Maximum Axial Position Changing RPM Method” the CVTis in the “Normal Driving Conditions” mode when it is not in the “HighTorque Driving Conditions” mode, and the transmission ratio of the CVTis from “its lowest (intial) transmission ratio” to the “transmissionratio immediately below its “highest (final) transmission ratio”.

For the “Normal Driving Conditions” mode, “the maximum rpm of the inputshaft” and “the maximum rpm of the output shaft” are limited to their“maximum axial position changing rpm value(s)” regardless of the input(gas pedal depression) of the driver. Under this setup, the “highest(final) transmission ratio” of the CVT can always be reached when theCVT is in the “Normal Driving Conditions” mode. The “Normal DrivingConditions” mode should be the mode that is active when the transmissionratio of the CVT is from “its lowest (intial) transmission ratio” to the“transmission ratio immediately below its highest (final) transmissionratio” during normal daily driving conditions.

For the “Alternate Maximum Axial Position Changing RPM Method” the CVTis in the “High Torque Driving Conditions” mode when the transmissionratio of the CVT is from “its lowest (intial) transmission ratio” to the“transmission ratio immediately below its “highest (final) transmissionratio” and the controlling computer of the CVT senses that its vehicleis in a “high torque required” situation, such as when the controllingcomputer senses that the depression of the gas pedal results in a lowerthan usual speed increase of the input shaft or when the gas pedal issuddenly/violently depressed. For the “High Torque Driving Conditions”mode, the “maximum rpm of the input shaft” and the “maximum rpm of theoutput shaft” are not limited to their “maximum axial position changingrpm value”.

For the “Alternate Maximum Axial Position Changing RPM Method” the CVTalso is in the “High Torque Driving Conditions” mode when the “HighTorque Driving Conditions” mode is manually selected by the driver.Examples of situations where manually selecting the “High Torque DrivingConditions” mode can be useful are driving uphill and pulling.

When the CVT is in the “High Torque Driving Conditions” mode,transmission ratio changing can still be performed as long as the speedof each shaft of “the cone(s) for which the axial position(s) is/arechanged” does not exceeded its/their “maximum axial position changingrpm value”.

For the “Alternate Maximum Axial Position Changing RPM Method” the CVTis in the “High Speed Driving Conditions” mode once it has reached “itsfinal (highest) transmission ratio”. For the “High Speed DrivingConditions” mode the “maximum rpm of the input shaft” and the “maximumrpm of the output shaft” are not limited, so as not to limit the speedof a vehicle to the “maximum axial position changing rpm value(s)” ofits CVT. When a CVT is in the “High Speed Driving Conditions” mode,transmission ratio changing can still be performed as long as the speedof each shaft of “the cone(s) for which the axial position(s) is/arechanged” does not exceeded its/their “maximum axial position changingrpm value”.

It is recommended that for the “Alternate Maximum Axial PositionChanging RPM Method” the “maximum axial position changing rpm value(s)”are higher than that/those of the “Maximum Axial Position Changing RPMMethod”. For the “Maximum Axial Position Changing RPM Method” it isrecommended that the “maximum axial position changing rpm value(s)” areselected so that it/they are never exceeded during “regular day to daydriving conditions” when the transmission ratio of the CVT is from the“lowest (intial) transmission ratio” to a “transmission ratio at which apredetermined cruising speed can be reached at a predeterminedreasonable engine rpm”. While for the “Alternate Maximum Axial PositionChanging RPM Method” it is recommended that the “maximum axial positionchanging rpm value(s)” are selected so that it/they are never exceededduring “regular day to day driving conditions” when the transmissionratio of the CVT is from its “lowest (intial) transmission ratio” to the“transmission ratio immediately below its highest (final) transmissionratio”.

For the “Maximum Axial Position Changing RPM Method” and the “AlternateMaximum Axial Position Changing RPM Method” it is recommended that both(which is preferred) or either (which is not preferred) of the followingare used: a) indication (such as alarm sound indication, message soundindication, visual signal indication, visual text indication, and/orhaptic indication, etc.) that is provided to the driver when a “maximumaxial position changing rpm value” is exceeded, and/or b) labeling ofthe rpm dial indicator to show the maximum engine rpm at which a“maximum axial position changing rpm value” will not be exceeded.

Item a) indication when a “maximum axial position changing rpm value” isexceeded, is used to inform the driver when “maximum axial positionchanging rpm value” is exceeded; the driver of a CVT should know(through manuals, instructional video, instructional text, instructionalaudio, etc.) that transmission ratio changing in the CVT cannot beperformed when a “maximum axial position changing rpm value” isexceeded. As such, here when a “maximum axial position changing rpmvalue” is exceeded, the driver knows that he/she needs to reduce theengine rpm (preferably when save and convenient) to allow fortransmission ratio changes in the CVT.

Indication when a “maximum axial position changing rpm value” isexceeded should be provided each time a “maximum axial position changingrpm value” is exceeded. And it is recommended that once triggered, thisindication remains active until no “maximum axial position changing rpmvalue” is exceeded anymore.

For Item b) the rpm dial indicator is marked to show the maximum enginerpm at which a “maximum axial position changing rpm value” will not beexceeded, a mark that says “CVT Maximum Transmission Ratio Changing RPM”can be used for example. Here because of the rpm dial indicator labeling(and if desired additional instruction through manuals, instructionalvideo, instructional text, instructional audio, etc.), the user of theCVT knows that transmission ratio changing cannot be continuouslyperformed when a “maximum axial position changing rpm value” isexceeded; and knows how much he/she needs to reduce the engine rpm whena “maximum axial position changing rpm value” is exceeded in order toallow for continuous/uninterrupted transmission ratio changes in theCVT.

The controlling computer can calculate and determine the engine rpm atwhich a “maximum axial position changing rpm value” is exceeded basedon: 1) the current transmission ratio, 2) the “maximum axial positionchanging rpm value” of the input shaft, 3) the “maximum axial positionchanging rpm value” of the output shaft, 4) the speed of the input shaftfor a given engine rpm at said current transmission ratio, and 5) thespeed of the output shaft for a given engine rpm at said currenttransmission ratio. Here a “maximum axial position changing rpm value”is exceeded for an engine rpm where 4) is greater than 2) and an enginerpm where 5) is greater than 3). The smaller engine rpm between theengine rpm where 4) is equal to 2) and the engine rpm where 5) is equalto 3) can be used as the engine rpm that is marked as the “CVT MaximumTransmission Ratio Changing RPM” on the rpm dial indicator.

The “CVT Maximum Transmission Ratio Changing RPM” changes with thetransmission ratio of the CVT, if the CVT has transmission ratios wherethe output shaft rotates faster than the input shaft. If it is notdesired to adjust the value indicated by the “CVT Maximum TransmissionRatio Changing RPM” mark with changes in the transmission ratio of theCVT, then the “CVT Maximum Axial Position Changing RPM” mark can simplybe an estimation. Here preferably a conservative estimation, whichensures that no “maximum axial position changing rpm value” is exceededfor all transmission ratios of the CVT when the value indicated by the“CVT Maximum Transmission Ratio Changing RPM” mark is not exceeded, isused for the “CVT Maximum Transmission Ratio Changing RPM” mark.

Alternately, if desired the value indicated by the “CVT MaximumTransmission Ratio Changing RPM” mark can be made to change with changesin the transmission ratio of the CVT, so that the “CVT MaximumTransmission Ratio Changing RPM” mark can be made to always indicate theactual maximum engine rpm value at which no “maximum axial positionchanging rpm value” is exceeded. Here animated displays such as LEDdisplays or LCD displays can be used for example.

If desired the “Maximum Axial Position Changing RPM Method” and the“Alternate Maximum Axial Position Changing RPM Method” can beimplemented so that they can be turned ON and OFF as desired by thedriver.

Another variation of the “Maximum Axial Position Changing RPM Method”,which is referred to as the “Alternate Maximum Axial Position ChangingRPM Method 2” is described below.

Like the “Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method 2”, “the maximumspeed of the input shaft at which the axial position of a cone mountedon it is changed” and “the maximum speed of the output shaft at whichthe axial position of a cone mounted on it is changed” are each limitedto their “maximum axial position changing rpm value”.

And like the “Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method 2”, the purpose ofthe “maximum axial position changing rpm value(s)” is to limit the rpm(speed) of the shafts at which axial position changing of “the conesmounted on them” is performed. As such, axial position changing of acone is only performed when the speed of the shaft of said cone has notexceeded its “maximum axial position changing rpm value”.

And like the “Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method 2”, in order toallow for reliable axial position changing of a cone of a CVT, the“maximum axial position changing rpm value” of the shaft of said coneshould be selected such that when said shaft is rotating at said“maximum axial position changing rpm value”, then axial positionchanging of said cone can be performed for all operating conditions ofits CVT, even when said shaft is suddenly fully accelerated.

And like for the “Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method 2”; for a CVT 6,the “maximum axial position changing rpm value” of a shaft should alsobe selected such that a complete sequence of steps of the “preferredtransmission ratio changing procedure for a CVT 6” can be performed forall operating condition of its CVT, even when said shaft is suddenlyfully accelerated.

But unlike the “Maximum Axial Position Changing RPM Method” and the“Alternate Maximum Axial Position Changing RPM Method”, for the“Alternate Maximum Axial Position Changing RPM Method 2” no engine rpmlimiting or any other engine performance limiting is performed.

For the “Alternate Maximum Axial Position Changing RPM Method 2” both(which is preferred) or either (which is not preferred) of the followingare used: a) indication (such as alarm sound indication, message soundindication, visual signal indication, visual text indication, and/orhaptic indication, etc.) that is provided to the driver when a “maximumaxial position changing rpm value” is exceeded, and/or b) labeling ofthe rpm dial indicator to show the maximum engine rpm at which a“maximum axial position changing rpm value” will not be exceeded.

Item a) indication when a “maximum axial position changing rpm value” isexceeded, is used to inform the driver when “maximum axial positionchanging rpm value” is exceeded; the driver of a CVT should know(through manuals, instructional video, instructional text, instructionalaudio, etc.) that transmission ratio changing in the CVT cannot beperformed when a “maximum axial position changing rpm value” isexceeded. As such, here when a “maximum axial position changing rpmvalue” is exceeded, the driver knows that he/she needs to reduce theengine rpm (preferably when save and convenient) to allow fortransmission ratio changes in the CVT.

Indication when a “maximum axial position changing rpm value” isexceeded should be provided each time a “maximum axial position changingrpm value” is exceeded. And it is recommended that once triggered, thisindication remains active until no “maximum axial position changing rpmvalue” is exceeded anymore.

For Item b) the rpm dial indicator is marked to show the maximum enginerpm at which a “maximum axial position changing rpm value” will not beexceeded, a mark that says “CVT Maximum Transmission Ratio Changing RPM”can be used for example. Here because of the rpm dial indicator labeling(and if desired additional instruction through manuals, instructionalvideo, instructional text, instructional audio, etc.), the user of theCVT knows that transmission ratio changing cannot be continuouslyperformed when a “maximum axial position changing rpm value” isexceeded; and knows how much he/she needs to reduce the engine rpm whena “maximum axial position changing rpm value” is exceeded in order toallow for continuous/uninterrupted transmission ratio changes in theCVT.

The controlling computer can calculate and determine the engine rpm atwhich a “maximum axial position changing rpm value” is exceeded basedon: 1) the current transmission ratio, 2) the “maximum axial positionchanging rpm value” of the input shaft, 3) the “maximum axial positionchanging rpm value” of the output shaft, 4) the speed of the input shaftfor a given engine rpm at said current transmission ratio, and 5) thespeed of the output shaft for a given engine rpm at said currenttransmission ratio. Here a “maximum axial position changing rpm value”is exceeded for an engine rpm where 4) is greater than 2) and an enginerpm where 5) is greater than 3). The smaller engine rpm between theengine rpm where 4) is equal to 2) and the engine rpm where 5) is equalto 3) can be used as the engine rpm that is marked as the “CVT MaximumTransmission Ratio Changing RPM” on the rpm dial indicator.

The “CVT Maximum Transmission Ratio Changing RPM” can change with thetransmission ratio of the CVT if the CVT has transmission ratios wherethe output shaft rotates faster than the input shaft. If it is notdesired to adjust the value indicated by the “CVT Maximum TransmissionRatio Changing RPM” mark with changes in the transmission ratio of theCVT, then the “CVT Maximum Axial Position Changing RPM” mark can simplybe an estimation. Here preferably a conservative estimation, whichensures that no “maximum axial position changing rpm value” is exceededfor all transmission ratios of the CVT when the value indicated by the“CVT Maximum Transmission Ratio Changing RPM” mark is not exceeded, isused for the “CVT Maximum Transmission Ratio Changing RPM” mark.

Alternately, if desired the value indicated by the “CVT MaximumTransmission Ratio Changing RPM” mark can be made to change with changesin the transmission ratio of the CVT, so that the “CVT MaximumTransmission Ratio Changing RPM” mark can be made to always indicate theactual maximum engine rpm value at which no “maximum axial positionchanging rpm value” is exceeded. Here animated displays such as LEDdisplays or LCD displays can be used for example.

For the “Alternate Maximum Axial Position Changing RPM Method 2” it isrecommended that the “maximum axial position changing rpm value(s)” areselected so that it or they (if different values are used for the inputshaft and the output shaft) are never exceeded during “regular day today driving conditions” when the transmission ratio of the CVT is fromthe “lowest (intial) transmission ratio” to the “highest (final)transmission ratio”.

For the “Alternate Maximum Axial Position Changing RPM Method 2” thefull power of the engine is always available when needed, such as duringhigh torque situations (which include: emergency situations where suddenacceleration is needed, driving uphill, pulling, etc.) and high speedsituations (speeds after the highest transmission ratio of the CVT hasbeen reached). Once a high torque situation or high speed situationwhere at least one “maximum axial position changing rpm value” isexceeded is over, the driver can simply reduce the engine rpm so that no“maximum axial position changing rpm value” is exceeded anymore so as toallow for transmission ratio changes in the CVT.

The value(s) for the “maximum axial position changing rpm value(s)” canbe obtained through experimentation. A ball park figure for the “maximumaxial position changing rpm value(s)” is between 3000 rpm to 4000 rpm.

The force needed for axial position changing of a cone and the shockloads for several “maximum axial position changing rpm values” ascalculated in the “Sample Calculations for Axial Position Changing”section are shown below: “maximum axial position changing rpmvalue”=3000 rpm: F_initial=40 lbs, h_dropping=0.38 cm; “maximum axialposition changing rpm value”=4000 rpm: F_initial=72 lbs, h_dropping=0.67cm; and “maximum axial position changing rpm value”=6000 rpm:F_initial=162 lbs, h_dropping=1.5 cm.

As can be seen from the previous paragraph the forces needed for axialposition changing of a cone and more importantly the shock loads arereduced significantly as the “maximum axial position changing rpm value”is reduced.

Calculations for the power consumption of a CVT due to transmissionratio changing is estimated below. Assuming that the width of a cone is6 inches, and during a 60 minute trip each cone is moved from itssmallest transmission diameter to its largest transmission diameter 100times, then the total distance moved for all 4 cones is: 100*4 cones*6inches*2=4800 inches=18.9 m. Assuming that the force needed to changethe axial position of a cone is 40 lbs (180 N) then the Work requiredfor transmission ratio changing of the CVT, Wcvt, is: Wcvt=180 N*18.9m=3402 Joules.

The power consumption of a car is estimated below. Assuming that for a60 minute (3600 seconds) trip, the car uses an average of 40 hp, thenthe Power consumed by the car, P, is: P=40 hp*735 Watts*3600seconds=105,840,000 Joules.

The % power consumption of the CVT as based on the earlier paragraphsis, % Pcvt, is: Pcvt=3402 J/105,840,000 J*100%=0.0032%. This is mostlikely less than the operating losses of a manual transmission due tomomentum losses, and the operating losses of an automatic transmissiondue to hydraulic clamping losses. In addition, when replacing a manualor automatic transmission can increase the efficiency of a car by 30%because of the increased transmission ratios.

In order to determine the speeds of the shafts for the “Maximum AxialPosition Changing RPM Method”, the “Alternate Maximum Axial PositionChanging RPM Method”, and the “Alternate Maximum Axial Position ChangingRPM Method 2”, speed sensors can be used.

Furthermore, the “Maximum Axial Position Changing RPM Method”, the“Alternate Maximum Axial Position Changing RPM Method”, and the“Alternate Maximum Axial Position Changing RPM Method 2” can be used forCVT's not described in this disclosure. All CVT's for which “loweringthe maximum rpm at which transmission ratio changing has to beperformed” is beneficial, can benefit from the “Maximum Axial PositionChanging RPM Method”, the “Alternate Maximum Axial Position Changing RPMMethod”, and the “Alternate Maximum Axial Position Changing RPM Method2”; this includes CVT's for which the axial position of pulley halvesinstead of cones have to be changed in order to change the transmissionratio for example.

The overall transmission ratio for a vehicle “that uses a CVT” or “thatuses a CVT and a Post Transmission” is controlled by a transmissionratio controller based on the speed of said vehicle by following apre-programmed ideal (but probably not always actual) “speed vstransmission ratio curve/equation(s)”.

For simplicity it is preferred that one “speed vs transmission ratiocurve” is used for all operating modes of a CVT and for all operatingconditions of a CVT; but if desired different “speed vs transmissionratio curves” for different “operation modes (Normal, High Torque, HighSpeed)” and/or “different operating conditions” can also be used.

For example, a CVT can have a “High Torque-Speed vs Transmission RatioCurve” and a “Low Torque-Speed vs Transmission Ratio Curve”; where the“High Torque-Speed vs Transmission Ratio Curve” is actuated when thecontrolling computer senses that the driver wants to accelerate thevehicle (as can be sensed by the controlling computer when the drivermaintains or increases the depressing of the gas pedal duringacceleration), and the “Low Torque-Speed vs Transmission Ratio Curve” isactuated when the controlling computer senses that the driver does notwant to accelerate the vehicle (as can be sensed by a controllingcomputer when the driver maintains the depression of the gas pedalduring cruising, or when the driver reduces the depression of the gaspedal).

If desired instead of only one “High Torque-Speed vs Transmission RatioCurve”, multiple “High Torque Speed vs Transmission Ratio Curves”, whichshapes can be based on the depression of the gas pedal can also be used.

For the “Maximum Axial Position Changing RPM Method” the transmissionratio of a vehicle is changed using the following “transmission ratioconfiguration according to speed setup”. For the “Normal DrivingConditions” mode, the transmission ratio of the CVT is increasedthroughout its transmission ratio range as the speed of the vehicle isincreased according to “its”/“its current” speed vs transmission ratiocurve. If the speed of the vehicle is increased further and a PostTransmission is used, the Post Transmission switches to high speedgearing(s) when its pre-set switching speed(s) have been reached.

Here in instances where at least one “maximum axial position changingrpm value” is exceeded during the CVT transmission ratio range, anincrease in the speed of the vehicle will not be accompanied by acorresponding increase in the transmission ratio of the CVT. It isrecommended but optional that here the Post Transmission, if used,switches gears to provide a gear ratio that better fits the current“speed vs transmission ratio curve” when relevant. And once no “maximumaxial position changing rpm value” is exceeded anymore, the PostTransmission returns to its “Normal Driving Conditions” mode gear ratioif required, and the transmission ratio controller will adjust thetransmission ratio of the CVT according to the selected “speed vstransmission ratio curve”.

If a “High Torque-Speed vs Transmission Ratio Curve” and a “LowTorque-Speed vs Transmission Ratio Curve” are used, then it isrecommended that the “High Torque-Speed vs Transmission Ratio Curve” isused when a CVT returns to “the state where no maximum axial positionchanging rpm value is exceeded” from “a state where at least one maximumaxial position changing rpm value is exceeded”; so that a larger torquefor acceleration is readily available when needed so as to increase theresponsiveness of the vehicle.

Using different “speed vs transmission ratio curves” for differentdriving situations, like the examples given above, can also be used forany other transmission.

An example of a CVT for a vehicle that uses the “Maximum Axial PositionChanging RPM Method” is describe below. For said CVT, the “maximum axialposition changing rpm value” for both the input shaft and the outputshaft are set to 3000 rpm; although the maximum speed that the inputshaft and the output shaft can rotate can be higher, such as 6000 rpmfor example. Here for both the input shaft and the output shaft, axialposition changing of a cone is only performed when they are rotating atspeeds of 0 to 3000 rpm regardless of the current operating modes.

For said CVT, the transmission ratio (output speed/input speedtransmission ratio) is from 1:4 to 1:1; 1:4 is the initial (lowest)transmission ratio and 1:1 is the final (highest) transmission ratio.When a vehicle starts-up from standstill, the CVT should always be atits initial (lowest) transmission ratio. Here if desired a “1:2 outputspeed/input speed gear reducer” can be used to modify the transmissionratio of the CVT, so that for the CVT itself a transmission ratio of 1:2to 2:1 can be used. If a “1:2 output speed/input speed gear reducer” isused, then it is recommended that it is positioned after the CVT, sothat the input torque and input speed of the engine to the CVT is notmodified by it. If a post transmission is used, then the “1:2 outputspeed/input speed gear reducer” can be part of the post transmission.

For said CVT, for the “Normal Driving Conditions” mode, for transmissionratios of 1:4 to 1:2, the maximum speeds of the input shaft and theoutput shaft are limited up to their “maximum axial position changingrpm value” of 3000 rpm regardless of the gas pedal depression (thetransmission ratio of 1:2 is the “transmission ratio at which apredetermined cruising speed can be reached at a predeterminedreasonable engine rpm”). This allows the transmission ratio to bechanged up to a transmission ratio of 1:2 even when the user of saidvehicle floors the gas pedal.

When a “large torque required situation” occurs for transmission ratiosof 1:4 to 1:2; then the CVT enters the “Low Transmission Ratio-HighTorque Driving Conditions” mode and the maximum speeds of the inputshaft and the output shaft will not be limited up to their “maximumaxial position changing rpm value” of 3000 rpm, so that the full powerof the engine is available. When the CVT is in the “Low TransmissionRatio-High Torque Driving Conditions” mode, transmission ratio changingcan still be performed as long as both the input shaft and the outputshaft do not exceeded their “maximum axial position changing rpm value”.

For transmission ratios of 1:2 to 1:1 of the “Normal Driving Conditions”mode, the maximum speeds of the input shaft and the output shaft are notlimited. But here when the input shaft or the output shaft exceed their“maximum axial position changing rpm value” of 3000 rpm, the CVT willswitch to the “High Transmission Ratio-High Torque Driving Conditions”mode.

The CVT is in the “High Speed Driving Conditions” mode when it is at itsfinal (highest) transmission ratio of 1:1. For the “High Speed DrivingConditions” mode the maximum rpm of the input shaft and the maximum rpmof the output shaft are not limited, so as not to limit the speed avehicle to the “maximum axial position changing rpm value”.

At a transmission ratio of 1:2, a cruising speed of about 70 mph can bereached at an input shaft speed, which is also the engine rpm, of about2000 rpm. If the maximum speeds of the input shaft and the output shaftare not limited to the “maximum axial position changing rpm value” of3000 rpm until a “transmission ratio at which a predetermined cruisingspeed can be reached at a predetermined reasonable engine rpm” has beenreached; then it is possible that the transmission ratio cannot bechanged when the user of the vehicle floors the gas pedal to above 3000rpm during start-up so that the transmission ratio remains at 1:4; ifso, a cruising speed of about 70 mph is reached at an input speed ofabout 4000 rpm. Cruising while the engine runs near redline can damagethe engine, and can be dangerous since almost no additional increase inspeed is available when suddenly required.

In order to extend the transmission ratio for the vehicle to above atransmission ratio of 1:1, a Post Transmission can be used. The PostTransmission can be a regular gear box that has a regular gearing andone or several high speed gearing(s); and its transmission ratiochanging ability is not limited by the “maximum axial position changingrpm value”.

The primary purpose of the Post Transmission is to provide additionaltransmission ratios for high speed situations of the vehicle. But ifused, it is recommended that a Post Transmission is also used to changethe transmission ratio for the vehicle during low speed situations ofthe vehicle in instances when the “maximum axial position changing rpmvalue” is exceeded but a transmission ratio that that better fits thecurrent “speed vs transmission ratio curve” can be provided by the PostTransmission. For a vehicle for which the diameters of the wheels are 25inches, an output shaft speed of 3000 rpm corresponds to vehicle speedof about 223 mph, as such a Post Transmission with high speed gearing(s)might not be necessary for most vehicles. But if desired, a PostTransmission can be used so that the transmission ratio range of the CVTcan be reduced, such as from “1:4 to 1:1” to “1:4 to 1:2” for example;this will reduce the size of the CVT.

The preferred method among the “Maximum Axial Position Changing RPMMethod”, the “Alternate Maximum Axial Position Changing RPM Method”, andthe “Alternate Maximum Axial Position Changing RPM Method 2”, is the“Alternate Maximum Axial Position Changing RPM Method 2” because of itssimplicity, but the other methods have merits as well.

Sample Calculations for Axial Position Changing

A rough sample calculation for a “Lever Indexing Mechanism 2” (describedin U.S. patent application Ser. No. 14/557,454) that is used to move a“cone with one torque transmitting member” axially is described below.Let's say for the cone with one torque transmitting member (alsoreferred to as “cone” or “the cone” in this section), the smallesttransmission diameter, Dsmall, is 3 inches and the largest transmissiondiameter, Dlarge, is 6 inches. In addition, the length of the cone fromDsmall to Dlarge is 6 inches, and the pitch length of a tooth of thetorque transmitting member is 0.25 inches. For this setup, the number ofteeth at Dsmall are approximately 75, and the number of teeth at Dlargeare approximately 150. As such the difference in the amount of teethfrom Dsmall to Dlarge is 75 teeth. Since a difference of 75 teeth isachieved over a length of 6 inches. The length (axial distance), S, thatthe cone has to be moved for a transmission diameter increase ordecrease of 1 tooth is: S=6 inches/75 teeth=0.08 inches.

And let's say the maximum rotating speed at which axial positionchanging of the cone is performed, rpm_max, is 3000 rpm, and axialposition changing of the cone has to be performed during a duration of ¾of a revolution of the cone. Then the maximum time, t, at which theaxial position of the cone can be changed is: t=(¾)/(3000 rpm)=0.00025minutes=0.015 seconds.

In order to calculate the acceleration, a, needed to move the cone weuse: S=0.5*a*t̂2, from which we get: a=2*S/t̂2. Using our earlier resultswe get: a=2*0.08/0.015̂2=711 inches/secondŝ2=18 meters/secondŝ2.

Assuming that the mass of the cone and its mechanisms to be movedaxially, m, is 5 kg; then the Force, F, needed to move the cone is:F=m*a=5*18=90 Newtons=20 lbs.

For a “Lever Indexing Mechanism 2”, the force to move a cone is providedby a pre-tensioned tension spring, and the force of the pre-tensionedtension spring decreases as its actuator lever rotates towards itsneutral position. The 20 lbs force required, as calculated above,assumes that a constant 20 lbs force is applied on the cone. In order tocompensate for this, the pre-tensioned tension spring needs to providean initial force, F_initial, of: 2*F=2*20 lbs=40 lbs. Here if the finalforce provided by the pre-tensioned tension spring is 0, then theaverage acceleration provided by the pre-tensioned tension spring isequal to the average acceleration provided by a constant 20 lbs force.The calculation described here is only a ballpark estimation; the actualinitial force needed can be easily obtained and refined throughexperimentation.

The impact velocity of the cone as it hits its stopping/final positionis: v_impact=a*t=18*0.015=0.27 meters/second. The dropping height,h_dropping, for the impact velocity can be determined from thefollowing: t=v_impact/gravity=0.27/9.81=0.028 seconds, andh_dropping=0.5*gravity*t̂2=0.5*9.81*0.028̂2=0.0038 meters=0.38 cm.

Using the same equations above except for different rpm values, we getthe following values for rpm_max=4000 rpm: F_initial=72 lbs,h_dropping=0.67 cm; and the following values for rpm_max=6000 rpm:F_initial=162 lbs, h_dropping=1.5 cm.

Detailed Design for Tensioning Pulleys Tensioning System

A detailed design for a “Tensioning Pulley Tensioning System” for apreferred CVT 6 (which here uses a Driving Cone 3C, a Driven Cone 5C,and a Transmission Belt 4C for one of its CVT4's) is shown as front-viewin FIG. 14 and as a partial top-view in FIG. 15. It has two verticalslider beams 16 which slide on slider rounds 17. In order to reduce thefriction between the vertical slider beams 16 and the slider rounds 17,each vertical slider beam 16 has two sleeve bearings 18.

On each vertical slider beam 16 a tensioning pulley is mounted; to theupper vertical slider beam 16 a tensioning pulley 14A is mounted, and tothe lower vertical slider beam 16 a tensioning pulley 13A is mounted(see FIG. 14).

In order to attach a tensioning pulley to a vertical slider beam 16, twoconnector plates 19 and two slider mounting plates 20 are used; see FIG.14 and FIG. 16 (which shows a partial sectional-view). Each connectorplate 19 is used to connect a slider mounting plate 20 to a verticalslider beam 16. Each slider mounting plate 20 is used to slide-ablymount a slider 21; and each slider 21 is used to attach the ends of apulley shaft 22 using a locking ring 23. A slider mounting plate 20 isshown by itself as a front-view in FIG. 17 and as a side-view in FIG.18. A slider 21, which preferably has low friction surfaces, is shown byitself as a front-view in FIG. 19 and as a side-view in FIG. 20.

The tensioning forces for the tensioning pulleys are provided bycompression springs 24, which push the lower vertical slider beam 16upwards and which push the upper vertical slider beam 16 downwards.

The compression springs 24 for the lower vertical slider beam 16 areinserted into slider rounds 17 and positioned between a fixed bottom endand the lower vertical slider beam 16. The fixed bottom end can be thebase of the slider rounds 17, or fasteners (locking rings, nuts, etc.)positioned/fixed below the lower vertical slider beam 16.

The compression springs 24 for the upper vertical slider beam 16 areinserted into slider rounds 17 and positioned between a fixed top endand the upper vertical slider beam 16. The fixed top end can be the topof the slider rounds 17, or fasteners (locking rings, nuts, etc.)positioned/fixed above the upper vertical slider beam 16. For the designshown in FIG. 14, locking rings 25 are used as the fixed top end.

In order to limit the movements of the tensioning pulleys to a rangethat allows for proper operation of the CVT, two maximum contractionstops 15A are used. One maximum contraction stop 15A is used to limitthe downward movement of the lower vertical slider beam 16. And theother maximum contraction stop 15A is used to limit the upward movementof the upper vertical slider beam 16.

Marked Disk for Determining Rotational Position

In order for the controlling computer of the CVT to know when to changethe axial position of a cone, a marked disk 26 can be used. A markeddisk 26 is a disk that has a marker 27, and a sensor 28 that isconnected to the controlling computer of the CVT and that can determinerotational position of the marker 27 (see FIG. 22). Examples for markers27 and sensors 28 are: a dimple and a mechanical switch, a lightsource/light reflector and a light sensor, a magnet and a magneticsensor, etc.

A marked disk 26 should be mounted so that it is fixed for rotationrelative to its cone, in FIG. 21 a set-screw is used to fix a markeddisk 26 to a cone 3D. The marker 27 of a marked disk 26 should bepositioned at the trailing end of the torque transmitting member of itscone, when said torque transmitting member is positioned at the smallesttransmission diameter of its cone; and the sensor 28 should bepositioned at the rotational position where the trailing end of thetorque transmitting member (when positioned at the smallest transmissiondiameter of its cone) disengages with its transmission belt. This isbecause axial position changing of a cone should be start when or afterthe trailing end of its torque transmitting member has disengaged withits transmission belt; and because for a smaller transmission diameter,the trailing end of the torque transmitting member can disengage “later”or “at the same time” compared to a larger transmission diameter(depending on the orientation of a cone).

Although the mounting of a marked disk 26 of the previous paragraph willreduce the axial position changing duration for larger transmissiondiameters of a cone, this should not be a problem, since the axialposition changing duration for a larger transmission diameter is longerthan that for a smaller transmission diameter. This is because theangular coverage of a torque transmitting member on the surface its conedecreases as the transmission diameter of its cone increases.

CVT 6 with Clutches

An alternate method for reducing the tension in the transmission belt ofa CVT 6 is to use a design where no adjusters 8 are used, but each coneof the CVT 6 is mounted on its shaft/spline using a clutch 29 (see FIG.23, the labeling of all other parts are identical to the labeling usedin FIG. 8). Here each clutch 29 can be used to controllably “lock itscone for rotation relative to its shaft/spline” or “unlock its cone soas to allow it to rotate relative to its shaft/spline”.

In order to change the axial position of a cone, the clutch 29 of saidcone is unlocked. Unlocking the clutch 29 of a cone reduces thetransmission belt tension of the CVT 4 of said cone; and allows the coneto freely rotate relative to its shaft/spline, so thattensioning/maintaining pulleys are not needed for compensating for therotations that occur during the axial position changing of said cone.Also here when there are two cones with different transmission diametersmounted on the same shaft/spline, at least one of said two cones needsto be unlocked by its clutch.

Adjusters for a CVT 6

Besides an adjuster motor, an indexing mechanism can also be used tocontrollably lock and unlock an adjuster of a CVT 6. If said indexingmechanism is used to lock and unlock the worm gear of the worm gear-geardrive of said adjuster; then the worm gear-gear drive can be selected ina manner such that the difference between and “the unlocking (rotating)force of the worm gear-gear drive when the worm gear is stationary” andthe “locking (frictional) force of the worm gear-gear drive when theworm gear is stationary” are small, so that the force required to lockand unlock the indexing mechanism is small. This results in a relativelycheap and very reliable adjuster.

An indexing mechanism, which can only lock in incremental steps, can beused to controllably lock and unlock an adjuster because: a) when thetransmission diameters of all cones mounted on a same shaft/spline areequal, an unlocked adjuster does not have to be locked. Here the cone ofsaid unlocked adjuster, which will be referred to as the unlocked cone,is simply a cone of the “CVT 4 for which transmission belt tension hasbeen reduced”, which is also the CVT 4 for which the axial position of acone is changed when axial position changing of a cone is initiated.Refer to the “Preferred transmission ratio changing procedure for a CVT6” section for details on the operation of an adjuster.

And indexing mechanism, which can only lock in incremental steps, can beused controllably lock and unlock an adjuster because: b) when anadjuster needs to be locked during “step e) Second axial positionchanging of a cone Option 2 of 2” of the “Preferred transmission ratiochanging procedure for a CVT 6”, rotations of the index wheel of theadjuster relative to its lock exist; this rotation, which is slowingdown, should allow the lock to enter a cavity of its index wheel. Herethe index wheel and its lock should be designed so that the saidrotation is sufficient for a lock to enter a cavity of its index wheel;if necessary a speed increasing gear train (such as a larger gearcoupled to a smaller gear for example) can be used to couple therotation of the worm gear to the index wheel.

Regarding the previous paragraph, during “step e) Second axial positionchanging of a cone Option 2 of 2”, when the transmission diameters ofthe cones mounted on a same shaft/spline are different and the adjusterof the “cone that is rotated in the direction that increases the tensionin the tense side of its transmission belt” needs to be locked; then inorder to compensate for having cones with different transmissiondiameters mounted on a same shaft/spline, first the “cone that is notrotated in the direction that increases the tension in the tense side ofits transmission belt”, which is currently locked and as such used fortorque transmission, needs to be unlocked so that it can rotate in thedirection that reduces the tension in its transmission belt. Once the“cone that needs to be rotated in the direction that reduces the tensionin its transmission belt” is unlocked in that direction, the “cone thatis rotated in the direction that reduces the tension in its transmissionbelt” still carries all or most of the torque transmitted until it hasreached the speed that compensates for having cones with differenttransmission diameters mounted on a same shaft/spline; note, here whilethe “cone that is rotated in the direction that reduces the tension inits transmission belt” speeds up, the “cone that is rotated in thedirection that increases the tension in the tense side of itstransmission belt” slows down. Here the friction of the worm gear-geardrive gives a time window until “the tension due torque transmission” isfully developed in the “adjuster to be locked”.

Here if desired, the “adjuster to be locked” can be locked after thespeed of its worm gear has slowed down, so as to reduce the shock-loadsduring locking. If this is desired, then a time delay from when theadjuster of the “cone that is rotated in the direction that reduces thetension in its transmission belt” is unlocked until when locking of the“adjuster to be locked” occurs can be used. The time delay does not haveto be accurate, but for better accuracy, the time delay can be based onthe current rpm and transmission ratio of its CVT 6. If used, it isrecommended the time delay is selected so that for all operatingconditions, locking of the adjuster occurs before the worm gear of the“adjuster to be locked” reverses direction, since by then the adjusterto be locked is subjected to the torque that is being transmitted by itsCVT 6 (instead of only the torque due to friction).

An adjuster that uses an indexing mechanism for controllably locking andunlocking its output shaft/spline is shown as a partial front-view inFIG. 24, as a partial side-view in FIG. 25, and as a partial top-view inFIG. 26. The adjuster is mounted on a spline 30, and is used to adjustthe rotational position of a cone positioned on a spline 30. In FIGS.24-26, the walls of housing 37 are cut open to show the inside of theadjuster.

The housing of the adjuster, which is labeled as housing 37, is fixedfor rotation relative to spline 30 but can slide axially relative tospline 30 (only relative axial movements between spline 30 and housing37 are allowed). The details for housing 37, such as the bearings, thespline cut-out profile to allow axial but not rotational movementrelative to spline 30, the counter-balance weight(s) to reducevibration, etc., are not shown. But somebody skilled in the art shouldbe able to construct housing 37 from the details provided here.

The adjuster of FIGS. 24-26 has a gear 32 that is fixed to an outputspline 31, so that gear 32 can be used to rotate output spline 31.Output spline 31 is shaped like hollow spline and is slid-on to spline30 and supported by parts of housing 37 (bearings, etc., which are notshown) in manner so as to be able to freely rotate and freely moveaxially relative to spline 30. Furthermore, output spline 31 issupported by parts of housing 37 in a manner so that output spline 31 isconcentric with spline 30.

In order to fix the axial position of gear 32 relative to output spline31, one or multiple set-screws (which are not shown) can be used. InFIGS. 24-26 the teeth of gear 32 are not shown, but obviously gear 32should have teeth.

Output spline 31 is mounted on housing 37 through bearings (which arenot shown) that allow output spline 31 to rotate relative to housing 37,but any other significant relative movements between output spline 31and housing 37 are not allowed. The front end of output spline 31 isused to attach a cone in a manner so that said cone is fixed forrotation and axial movements relative to output spline 31; for suchpurpose, the front end of output spline 31 can also have one or multipleset-screws (not shown).

Gear 32 is coupled to a worm gear 33. Gear 32 and worm gear 33 should beselected so that the worm gear-gear drive is not self-locking (whichmeans that gear 32 can drive worm gear 33). Worm gear 33 is fixed to ashaft 34 in a manner so that worm gear 33 can be used to rotate shaft34. Shaft 34 is mounted to housing 37 so that it can rotate about itsaxis of rotation relative to housing 37, but any other significantrelative movements between shaft 34 and housing 37 are not allowed.

Also fixed for axial and rotational movements to shaft 34 is an indexwheel 35. Since index wheel 35 is fixed for rotation relative to shaft34, index wheel 35 can be used to lock and unlock the rotationalmovements of shaft 34. In order to fulfill its purpose, index wheel 35has circumferential cavities (the cavities are shown in FIG. 25 but notin FIGS. 24 and 26).

And fixed to housing 37 is a locking mechanism 36 that can be used tolock and unlock index wheel 35. Locking mechanism 36 comprises of a lockthat can be inserted into a cavity of index wheel 35, a spring, and asolenoid. The lock is pushed towards the index wheel cavities so that itcan enter the index wheel cavities (one cavity at a time) by the spring,and the lock can be controllably pulled out of an index wheel cavity bythe solenoid.

When the lock is in a cavity of index wheel 35, index wheel 35, and assuch also the adjuster is locked; and when the lock is not in a cavityof index wheel 35, index wheel 35 and as such also the adjuster, isunlocked.

Instead of using a spring and a solenoid to lock and unlock an indexwheel, a pneumatic/hydraulic actuator with or without a spring, or otherdevices that can lock and unlock an index wheel can also be used.

Instead of using an indexing mechanism, an adjuster can also use a brakeor an electric motor. An adjuster using a brake is shown in FIGS. 27-29,where a brake disk 38 and braking shoe mechanism 39 are used in-place ofindex wheel 35 and locking mechanism 36. And an adjuster using anadjuster motor, which is preferably an electric motor, is shown in FIGS.30-32, where an electric motor 40 is used to rotate shaft 34. All partsof the “adjuster shown in FIGS. 27-29” and the “adjuster shown in FIGS.30-32” that are not mentioned in this paragraph are identical to the“adjuster shown in FIGS. 24-26” and use the same numbering and labeling.

An adjuster that uses an indexing mechanism for which a speed increasinggear train (such as a larger gear coupled to a smaller gear for example)is used to couple the rotation of the worm gear to the index wheel isshown in FIGS. 33-35. In FIGS. 33 and 35, the speed increasing geartrain is labeled as gear train 41 and it is fixed to housing 37 (FIG. 34does not show gear train 41 since it is behind index wheel 35). Allparts of the “adjuster shown in FIGS. 33-35” except for gear train 41are identical to the “adjuster shown in FIGS. 24-26” and use the samenumbering and labeling.

The adjusters of this application are basically used as a clutch, assuch they can also be used clutches for other applications. For otherapplications, when desired, the housing of the adjuster can be constructso that it is fixed for all relative movements to its shaft or spline;unlike the example described in the paragraphs above, where the housingof the adjuster can slide axially relative to its spline.

PREFERRED EMBODIMENT OF THE INVENTION Best Mode

The preferred method among the “Maximum Axial Position Changing RPMMethod”, the “Alternate Maximum Axial Position Changing RPM Method”, andthe “Alternate Maximum Axial Position Changing RPM Method 2”, is the“Alternate Maximum Axial Position Changing RPM Method 2” because of itssimplicity, but the other methods have merits as well.

CONCLUSION, RAMIFICATIONS, AND SCOPE

Disclosed in this disclosure are methods that can be used to “limit themaximum shaft rpm (speed) at which axial position changing of a variatormounted on it is performed to a “maximum axial position changing rpmvalue” for all variator mounted shafts of a CVT, while still allowing asafe driving experience and also allowing the driver to use the fullpower of the engine when needed. The methods of this disclosure are: the“Maximum Axial Position Changing RPM Method”, the “Alternate MaximumAxial Position Changing RPM Method”, and the “Alternate Maximum AxialPosition Changing RPM Method 2”.

The methods of this disclosure can also be applied to CVT's that useother variators besides cone assemblies, such as push belt pulleys forexample. Push belt pulleys are variators that consist of two pulleyhalves for which either one pulley half or both pulley halves are movedaxially in order to change the pulley's transmission diameter. For theseCVT's a “maximum axial position changing rpm value” of a push beltpulley refers to the maximum rpm at which the axial position of one orboth pulley halves of the push belt pulley is/are changed.

Although the description of the “Maximum Axial Position Changing RPMMethods” Section is a for a CVT that uses one or several variators onboth the input shaft and the output shaft (such as a CVT 4, CVT 6, orany other CVT where one or several variators on the input shaft is/arecoupled to one or several variators on the output shaft); the methods ofthis disclosure can also be applied to CVT's for which “a variator” or“several variator(s)” are only mounted on either the input shaft or theoutput shaft (such a CVT 3, a CVT where a variator is coupled to atransmission pulley, or any other CVT that uses only one shaft on whichvariator(s) is/are mounted). Since only the shafts on which variator(s)are mounted have a “maximum axial position changing rpm value”, forthese CVT's only one shaft has a “maximum axial position changing rpmvalue”.

Furthermore, the description of the “Maximum Axial Position Changing RPMMethods” Section also applies to CVT's that use splines instead ofshafts. For the methods of this disclosure the terms spline, shaft, orany other means for rotatably mounting a variator, can be usedinterchangeably; since for said methods, they serve the same function,and said methods can be applied to a CVT in the same manner regardlesswhether said CVT uses splines, shafts, or any other means for rotatablymounting a variator.

The “Maximum Axial Position Changing RPM Methods” Section contains thefollowing sentence: For the “Maximum Axial Position Changing RPMMethod”, “the maximum speed of the input shaft at which the axialposition of a cone mounted on it is changed” and “the maximum speed ofthe output shaft at which the axial position of a cone mounted on it ischanged” are each limited to their “maximum axial position changing rpmvalue”. This sentence can be rewritten as: For the “Maximum AxialPosition Changing RPM Method”, the maximum shaft/spline rpm (speed) atwhich axial position changing of a variator mounted on it is performedis limited to “maximum axial position changing rpm value” for allvariator mounted shafts/splines of a CVT. The rewritten sentence appliesto CVT's with two variator mounted shafts/splines, such as a CVT 6, andCVT's with only one variator mounted shaft/spline. The same sentence canalso be rewritten in the same manner for the “Alternate Maximum AxialPosition Changing RPM Method” and the “Alternate Maximum Axial PositionChanging RPM Method 2”

The “Maximum Axial Position Changing RPM Methods” Section contains thefollowing sentence: For this transmission ratio range of the “NormalDriving Conditions” mode, “the maximum rpm of the input shaft” and “themaximum rpm of the output shaft” are limited to their “maximum axialposition changing rpm value” regardless of the input (gas pedaldepression) of the driver. This sentence can be rewritten as: For thistransmission ratio range of the “Normal Driving Conditions” mode, themaximum rpm of all variator mounted shafts/splines is/are limited totheir “maximum axial position changing rpm value” regardless of theinput (gas pedal depression) of the driver. The rewritten sentenceapplies to CVT's with two variator mounted shafts/splines, such as a CVT6, and CVT's with only one variator mounted shaft/spline. Allcorresponding sentences of the “Maximum Axial Position Changing RPMMethods” Section can also be rewritten in the same manner.

The preferred embodiment of the invention is the “Alternate MaximumAxial Position Changing RPM Method 2” described in the “Maximum AxialPosition Changing RPM Methods” Section. As a claim, this invention canbe described as: A method that can be used to “limit the maximumshaft/spline rpm (speed) at which axial position changing of a variatormounted on it is performed to a “maximum axial position changing rpmvalue” for all variator mounted shafts/splines of a CVT, while stillallowing a safe driving experience and also allowing the driver to usethe full power of the engine when needed, by: a) assigning a said“maximum axial position changing rpm value” to each variator mountedshaft/spline; b) only changing the axial position of a variator when the“maximum axial position changing rpm value” of the shaft/spline of saidvariator is not exceeded; and c) providing indication when a said“maximum axial position changing rpm value” is exceeded, so that thedriver of said CVT knows that he/she needs to reduce the rpm of theengine in order to allow for continuous/uninterrupted transmission ratiochanges in said CVT.

Another claim for the “Alternate Maximum Axial Position Changing RPMMethod 2” is as follows: A method that can be used to “limit the maximumshaft/spline rpm (speed) at which axial position changing of a variatormounted on it is performed to a “maximum axial position changing rpmvalue” for all variator mounted shafts/splines of a CVT, while stillallowing a safe driving experience and also allowing the driver to usethe full power of the engine when needed, by: a) assigning a said“maximum axial position changing rpm value” to each variator mountedshaft/spline; b) only changing the axial position of a variator when the“maximum axial position changing rpm value” of the shaft/spline of saidvariator is not exceeded; and c) labeling the rpm dial indicator to showthe maximum engine rpm at which a “maximum axial position changing rpmvalue” will not be exceeded, so that the user of said CVT knows whentransmission ratio changing cannot be continuously performed because atleast one said “maximum axial position changing rpm value” is exceeded;and knows how much he/she needs to reduce the engine rpm when at leastone said “maximum axial position changing rpm value” is exceeded inorder to allow for continuous/uninterrupted transmission ratio changesin said CVT.

While my above description contains many specificities, these should notbe construed as limitations on the scope, but rather as anexemplification of one or several embodiment(s) thereof. Many othervariations are possible.

Accordingly, the scope should be determined not by the embodiment(s)illustrated, but by the appended claims and their legal equivalents.

I claim:
 1. A method that can be used to “limit the maximum shaft/splinerpm (speed) at which axial position changing of a variator mounted on itis performed to a “maximum axial position changing rpm value” for allvariator mounted shafts/splines of a CVT, while still allowing a safedriving experience and also allowing the driver to use the full power ofthe engine when needed, by: a) assigning a said “maximum axial positionchanging rpm value” to each variator mounted shaft/spline; b) onlychanging the axial position of a variator when the “maximum axialposition changing rpm value” of the shaft/spline of said variator is notexceeded; c) providing indication when a said “maximum axial positionchanging rpm value” is exceeded, so that the driver of said CVT knowsthat he/she needs to reduce the rpm of the engine in order to allow forcontinuous/uninterrupted transmission ratio changes in said CVT.
 2. Amethod that can be used to “limit the maximum shaft/spline rpm (speed)at which axial position changing of a variator mounted on it isperformed to a “maximum axial position changing rpm value” for allvariator mounted shafts/splines of a CVT, while still allowing a safedriving experience and also allowing the driver to use the full power ofthe engine when needed, by: a) assigning a said “maximum axial positionchanging rpm value” to each variator mounted shaft/spline; b) onlychanging the axial position of a variator when the “maximum axialposition changing rpm value” of the shaft/spline of said variator is notexceeded; c) providing indication when a said “maximum axial positionchanging rpm value” is exceeded, so that the driver of said CVT knowsthat he/she needs to reduce the rpm of the engine in order to allow forcontinuous/uninterrupted transmission ratio changes in said CVT.